Uplink resources for beam recovery

ABSTRACT

Methods, systems, and devices for wireless communication are described. Uplink resources may be allocated for transmissions of beam recovery messages. For example, a user equipment (UE) communicating in a system that supports beamformed transmissions may receive a configuration for resources from a base station, where the resources may be used for beam recovery signaling. The UE may identify a beam failure on one or more active beams used to communicate with the base station, and the UE may transmit a beam recovery message to the base station. In such cases, the beam recovery message may be transmitted according to the configuration received from the base station such that the beam recovery message is transmitted using the beam recovery resources. In some cases, the configuration may be received at the UE via radio resource control (RRC) signaling or via a system information broadcast from the base station.

CROSS REFERENCES

The present Application for Patent claims priority to U.S. ProvisionalPatent Application No. 62/457,704 by Nagaraja, et al., entitled “UplinkResources For Beam Recovery,” filed Feb. 10, 2017, assigned to theassignee hereof, and is hereby expressly incorporated by referenceherein in its entirety.

BACKGROUND

The following relates generally to wireless communication, and morespecifically to uplink resources for beam recovery.

Wireless communications systems are widely deployed to provide varioustypes of communication content such as voice, video, packet data,messaging, broadcast, and so on. These systems may be capable ofsupporting communication with multiple users by sharing the availablesystem resources (e.g., time, frequency, and power). Examples of suchmultiple-access systems include code division multiple access (CDMA)systems, time division multiple access (TDMA) systems, frequencydivision multiple access (FDMA) systems, and orthogonal frequencydivision multiple access (OFDMA) systems, (e.g., a Long Term Evolution(LTE) system, or a New Radio (NR) system). A wireless multiple-accesscommunications system may include a number of base stations or accessnetwork nodes, each simultaneously supporting communication for multiplecommunication devices, which may be otherwise known as user equipment(UE).

Some wireless communications systems (e.g., NR systems) may operate infrequency ranges that are associated with beamformed transmissionsbetween wireless devices. For example, transmissions in millimeter wave(mmW) frequency ranges and may be associated with increased signalattenuation (e.g., path loss) as compared to transmissions in non-mmWfrequency ranges. As a result, signal processing techniques such asbeamforming may be used to combine energy coherently and overcome thepath losses in these systems. In some cases, one or more active beamsbetween two wireless devices may become misaligned. Upon detecting sucha misalignment (or beam failure), a UE may attempt to access uplinkresources to reconnect with the serving cell, but some uplink resourcesused to convey the attempted beam recovery may be associated withlimited throughput or high latency, or both. Thus, improved techniquesfor uplink resource allocation for beam recovery may be desired.

SUMMARY

The described techniques relate to improved methods, systems, devices,or apparatuses that support uplink resources for beam recovery.Generally, the described techniques provide for configuration ofdedicated resources for one or more UEs to convey a beam recoveryrequest to a base station. In some cases, these resources may bedynamically or semi-statically configured by the base station andcommunicated to one or more UEs. Using techniques described herein, a UEmay determine a beam failure on one or more active beams (e.g., due tomisalignment) and use the configured resources to send the beam recoverymessage. In some aspects, one or more downlink beams (e.g., each ofwhich may have an associated reference signal) may be associated withequivalent uplink resources over which the UE may convey the beamrecovery message. In some examples, the beam recovery message maycontain measurements or other information which may assist the basestation in reconnecting with the UE.

A method of wireless communication is described. The method may includereceiving a configuration for beam recovery resources, identifying abeam failure of one or more active beams used to communicate with a basestation, and transmitting, according to the received configuration, abeam recovery message to the base station using the beam recoveryresources based at least in part on the identified beam failure.

An apparatus for wireless communication is described. The apparatus mayinclude means for receiving a configuration for beam recovery resources,means for identifying a beam failure of one or more active beams used tocommunicate with a base station, and means for transmitting, accordingto the received configuration, a beam recovery message to the basestation using the beam recovery resources based at least in part on theidentified beam failure.

Another apparatus for wireless communication is described. The apparatusmay include a processor, memory in electronic communication with theprocessor, and instructions stored in the memory. The instructions maybe operable to cause the processor to receive a configuration for beamrecovery resources, identify a beam failure of one or more active beamsused to communicate with a base station, and transmit, according to thereceived configuration, a beam recovery message to the base stationusing the beam recovery resources based at least in part on theidentified beam failure.

A non-transitory computer readable medium for wireless communication isdescribed. The non-transitory computer-readable medium may includeinstructions operable to cause a processor to receive a configurationfor beam recovery resources, identify a beam failure of one or moreactive beams used to communicate with a base station, and transmit,according to the received configuration, a beam recovery message to thebase station using the beam recovery resources based at least in part onthe identified beam failure.

Some examples of the method, apparatus, and non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for receiving a message from the basestation in response to the transmitted beam recovery message, themessage comprising an indication of a set of reference signals for beamrefinement. In some examples of the method, apparatus, andnon-transitory computer-readable medium described above, transmittingthe beam recovery message to the base station comprises: transmittingthe beam recovery message on one or more resources in one or more beamdirections.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, receiving the configurationfor the beam recovery resources comprises: receiving the configurationas part of radio resource control (RRC) signaling from the base stationor as part of a system information broadcast from the base station. Someexamples of the method, apparatus, and non-transitory computer-readablemedium described above may further include processes, features, means,or instructions for receiving an indication that enables the use of thebeam recovery resources for the transmission of the beam recoverymessage, wherein transmitting the beam recovery message may be based atleast in part on the indication.

Some examples of the method, apparatus, and non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for receiving an indication thatdisables the use of the beam recovery resources for the transmission ofthe beam recovery message, wherein transmitting the beam recoverymessage may be based at least in part on the indication. In someexamples of the method, apparatus, and non-transitory computer-readablemedium described above, the configuration comprises a UE-specificconfiguration for the beam recovery resources. In some examples of themethod, apparatus, and non-transitory computer-readable medium describedabove, the configuration comprises an indication of a plurality of beamsfor transmitting the beam recovery message, the indication based atleast in part on a signal-to-noise ratio (SNR) associated with the UE,and wherein transmitting the beam recovery message comprises:transmitting the beam recovery message using at least one of theplurality of beams.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the configuration comprises anindication of a system frame number (SFN) corresponding to the beamrecovery resources, a subframe index (SFI) corresponding to the beamrecovery resources, a periodicity corresponding to the beam recoveryresources, one or more resource elements (REs) corresponding to the beamrecovery resources, or a combination thereof.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the beam recovery resourcesoccupy a first region of resources that may be different from a secondregion of resources allocated for transmission of a random accessmessage. In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the configuration comprises anindication of a mapping between a downlink beam from the base stationand the beam recovery resources.

Some examples of the method, apparatus, and non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for transmitting, according to thereceived configuration, a scheduling request (SR) to the base stationusing the beam recovery resources. Some examples of the method,apparatus, and non-transitory computer-readable medium described abovemay further include processes, features, means, or instructions forperforming measurements of a set of reference signals, the set ofreference signals associated with the one or more active beams, whereinthe beam recovery message comprises a measurement report based at leastin part on the performed measurements.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the measurement reportcomprises a reference signal received power (RSRP), a reference signalreceived quality (RSRQ), a channel quality indicator (CQI), a precodingmatrix indicator (PMI) a rank, or a combination thereof. In someexamples of the method, apparatus, and non-transitory computer-readablemedium described above, the set of reference signals comprises asynchronization signal, a mobility reference signal, a channel stateinformation reference signal (CSI-RS), or a combination thereof.

Some examples of the method, apparatus, and non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for determining a mobility conditionassociated with the UE, the mobility condition of the UE comprising adirection of the UE relative to the base station, an orientation of theUE, a distance from the base station, or a combination thereof, whereinthe beam recovery message comprises an indication of the mobilitycondition. Some examples of the method, apparatus, and non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for identifying antenna arrayinformation corresponding to one or more antenna arrays located at theUE, wherein the beam recovery message comprises an indication of theantenna array information.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the antenna array informationcomprises a number of antenna arrays located at the UE. Some examples ofthe method, apparatus, and non-transitory computer-readable mediumdescribed above may further include processes, features, means, orinstructions for determining an identity of a downlink beam from thebase station, wherein the beam recovery message comprises an indicationof the identity of the downlink beam.

A method of wireless communication is described. The method may includecommunicating with one or more UEs using one or more active beams,transmitting a configuration for beam recovery resources, and receivingone or more beam recovery messages on the beam recovery resources, theone or more beam recovery messages indicating a beam failure of at leastone of the one or more active beams.

An apparatus for wireless communication is described. The apparatus mayinclude means for communicating with one or more UEs using one or moreactive beams, means for transmitting a configuration for beam recoveryresources, and means for receiving one or more beam recovery messages onthe beam recovery resources, the one or more beam recovery messagesindicating a beam failure of at least one of the one or more activebeams.

Another apparatus for wireless communication is described. The apparatusmay include a processor, memory in electronic communication with theprocessor, and instructions stored in the memory. The instructions maybe operable to cause the processor to communicate with one or more UEsusing one or more active beams, transmit a configuration for beamrecovery resources, and receive one or more beam recovery messages onthe beam recovery resources, the one or more beam recovery messagesindicating a beam failure of at least one of the one or more activebeams.

A non-transitory computer readable medium for wireless communication isdescribed. The non-transitory computer-readable medium may includeinstructions operable to cause a processor to communicate with one ormore UEs using one or more active beams, transmit a configuration forbeam recovery resources, and receive one or more beam recovery messageson the beam recovery resources, the one or more beam recovery messagesindicating a beam failure of at least one of the one or more activebeams.

Some examples of the method, apparatus, and non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for transmitting a message to a UE inresponse to the received one or more beam recovery messages, the messagecomprising an indication of a set of reference signals for beamrefinement. Some examples of the method, apparatus, and non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for receiving the one or more beamrecovery messages comprises receiving a measurement report from the UE.Some examples of the method, apparatus, and non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for determining a transmit beamdirection based at least in part on the measurement report. Someexamples of the method, apparatus, and non-transitory computer-readablemedium described above may further include processes, features, means,or instructions for transmitting the message to the UE using thedetermined transmit beam direction.

Some examples of the method, apparatus, and non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for performing a measurement on uplinksignals over the one or more active beams. Some examples of the method,apparatus, and non-transitory computer-readable medium described abovemay further include processes, features, means, or instructions fordetermining a transmit beam direction based at least in part on themeasurement of the uplink signals, wherein transmitting the message tothe UE may be based at least in part on the transmit beam direction. Insome examples of the method, apparatus, and non-transitorycomputer-readable medium described above, receiving the one or more beamrecovery messages comprises: receiving the one or more beam recoverymessages on a set of resources in one or more receive beam directions.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, transmitting the configurationfor the beam recovery resources comprises: transmitting theconfiguration as part of RRC signaling or as part of a systeminformation broadcast. Some examples of the method, apparatus, andnon-transitory computer-readable medium described above may furtherinclude processes, features, means, or instructions for transmitting anindication that enables the use of the beam recovery resources for theone or more beam recovery messages, wherein receiving the one or morebeam recovery messages may be based at least in part on the indication.

Some examples of the method, apparatus, and non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for transmitting an indication thatdisables the use of the beam recovery resources for the one or more beamrecovery messages, wherein receiving the one or more beam recoverymessages may be based at least in part on the indication. In someexamples of the method, apparatus, and non-transitory computer-readablemedium described above, identifying a traffic level associated with asubset of the one or more UEs, wherein transmitting the configurationfor the beam recovery resources comprises: transmitting theconfiguration to the subset of the one or more UEs based at least inpart on the identified traffic level.

Some examples of the method, apparatus, and non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for identifying an SNR associated witha UE, wherein the configuration comprises a UE-specific configuration ofbeam recovery resources based at least in part on the identified SNR. Insome examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the configuration comprises anindication of a plurality of beams for each of the one or more beamrecovery messages.

Some examples of the method, apparatus, and non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for identifying a payload associatedwith an uplink transmission from the one or more UEs, wherein theconfiguration comprises an indication of additional beam recoveryresources allocated for the one or more beam recovery messages based atleast in part on the identified payload. In some examples of the method,apparatus, and non-transitory computer-readable medium described above,the beam recovery resources may be associated with a first region ofresources that may be different from a second region resources allocatedfor transmission of a random access message.

Some examples of the method, apparatus, and non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for identifying one or more referencesignals associated with a set of downlink beams. Some examples of themethod, apparatus, and non-transitory computer-readable medium describedabove may further include processes, features, means, or instructionsfor identifying a mapping between the beam recovery resources and theset of downlink beams based at least in part on the one or morereference signals, wherein the configuration comprises an indication ofthe mapping.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an example of a system for wireless communicationthat supports uplink resources for beam recovery in accordance withaspects of the present disclosure;

FIG. 2 illustrates an example of a system for wireless communicationthat supports uplink resources for beam recovery in accordance withaspects of the present disclosure;

FIG. 3 illustrates an example of a resource grid in a system thatsupports uplink resources for beam recovery in accordance with aspectsof the present disclosure;

FIG. 4 illustrates an example of a process flow in a system thatsupports uplink resources for beam recovery in accordance with aspectsof the present disclosure;

FIGS. 5 through 7 show block diagrams of a device that supports uplinkresources for beam recovery in accordance with aspects of the presentdisclosure;

FIG. 8 illustrates a block diagram of a system including a UE thatsupports uplink resources for beam recovery in accordance with aspectsof the present disclosure;

FIGS. 9 through 11 show block diagrams of a device that supports uplinkresources for beam recovery in accordance with aspects of the presentdisclosure;

FIG. 12 illustrates a block diagram of a system including a base stationthat supports uplink resources for beam recovery in accordance withaspects of the present disclosure; and

FIGS. 13 through 18 illustrate methods for uplink resources for beamrecovery in accordance with aspects of the present disclosure.

DETAILED DESCRIPTION

Some wireless communication systems may operate in frequency ranges thatsupport beamformed transmissions between wireless devices. For example,communications in mmW frequency bands may experience increased signalattenuation (e.g., path loss). As a result, signal processing techniquessuch as beamforming may be used to combine energy coherently andovercome the path losses in these systems. In such systems, wirelessdevices, such as a UE and base station, may be able to communicate overone or more active beams, which may correspond to a transmit beam usedat the transmitting device and a receive beam at a receiving device(e.g., comprising a beam pair). In some cases, the active beam pair(s)may become misaligned (e.g., due to beam switch failure or signalblockage) such that the UE and base station may not be able tocommunicate over the obstructed active beam pair(s) due to the beamfailure. A UE may accordingly detect the beam failure (e.g., bymonitoring a subset of reference signals) on the active beams used tocommunicate with the base station.

To reconnect with the serving cell, the UE may need resources, which maybe defined in terms of time, frequency, and/or a beam, to transmit abeam recovery request (e.g., a beam failure recovery request). In asystem supporting multi-beam operation, certain uplink resources may beused by the UE to reconnect with the cell. For example, a UE may defaultto using SR resources or random access channel (RACH) resources toconvey such a beam recovery request. But these resources may beassociated with limited throughput and/or high latency (e.g., becausethey may be contention-based resources or may be available with arelatively low periodicity). Accordingly, some systems may support theconfiguration of one or more sets of dedicated resources for a UE (ormultiple UEs) to use to transmit beam recovery requests, which mayenable faster, more robust, and more efficient recovery.

The techniques described herein generally provide for the allocation ofdedicated resources for the transmission of a beam recovery message. Forexample, a UE communicating in a system that supports beamformedtransmissions may receive a configuration for uplink resources from abase station, where the uplink resources may be dedicated for beamrecovery signaling. The UE may identify a beam failure (e.g., due topath loss or interference) on one or more active beams used tocommunicate with the base station, and the UE may transmit a beamrecovery message to the base station. In such cases, the beam recoverymessage may be transmitted according to the configuration received fromthe base station such that the beam recovery message is transmittedusing the dedicated beam recovery resources. In some cases, theconfiguration may be received at the UE via RRC signaling or via asystem information broadcast from the base station. Additionally, theuse of the beam recovery resources may be enabled or disabled by anindication from the base station (e.g., using lower layer signaling),where the UE may transmit the beam recovery message on different sets ofresources based on whether the beam recovery resources are enabled ordisabled. Following the transmission of the beam recovery requestmessage, the UE may monitor for a response to the beam recovery requestmessage from the base station.

Aspects of the disclosure are initially described in the context of awireless communications system. Further examples are then provided of anuplink resource grid and a process flow for the transmission of a beamrecovery message. Aspects of the disclosure are further illustrated byand described with reference to apparatus diagrams, system diagrams, andflowcharts that relate to uplink resources for beam recovery.

FIG. 1 illustrates an example of a wireless communications system 100 inaccordance with various aspects of the present disclosure. The wirelesscommunications system 100 includes base stations 105, UEs 115, and acore network 130. In some examples, the wireless communications system100 may be an LTE, LTE-Advanced (LTE-A) network, or an NR network. Insome cases, wireless communications system 100 may support enhancedbroadband communications, ultra-reliable (i.e., mission critical)communications, low latency communications, and communications withlow-cost and low-complexity devices. Wireless communications system 100may support the efficient use of uplink resources for beam recovery.

Base stations 105 may wirelessly communicate with UEs 115 via one ormore base station antennas. Each base station 105 may providecommunication coverage for a respective geographic coverage area 110.Communication links 125 shown in wireless communications system 100 mayinclude uplink transmissions from a UE 115 to a base station 105, ordownlink transmissions, from a base station 105 to a UE 115. Controlinformation and data may be multiplexed on an uplink channel or downlinkaccording to various techniques. Control information and data may bemultiplexed on a downlink channel, for example, using time divisionmultiplexing (TDM) techniques, frequency division multiplexing (FDM)techniques, or hybrid TDM-FDM techniques. In some examples, the controlinformation transmitted during a transmission time interval (TTI) of adownlink channel may be distributed between different control regions ina cascaded manner (e.g., between a common control region and one or moreUE-specific control regions).

UEs 115 may be dispersed throughout the wireless communications system100, and each UE 115 may be stationary or mobile. A UE 115 may also bereferred to as a mobile station, a subscriber station, a mobile unit, asubscriber unit, a wireless unit, a remote unit, a mobile device, awireless device, a wireless communications device, a remote device, amobile subscriber station, an access terminal, a mobile terminal, awireless terminal, a remote terminal, a handset, a user agent, a mobileclient, a client, or some other suitable terminology. A UE 115 may alsobe a cellular phone, a personal digital assistant (PDA), a wirelessmodem, a wireless communication device, a handheld device, a tabletcomputer, a laptop computer, a cordless phone, a personal electronicdevice, a handheld device, a personal computer, a wireless local loop(WLL) station, an Internet of things (IoT) device, an Internet ofEverything (IoE) device, a machine type communication (MTC) device, anappliance, an automobile, or the like.

The core network 130 may provide user authentication, accessauthorization, tracking, Internet Protocol (IP) connectivity, and otheraccess, routing, or mobility functions. At least some of the networkdevices, such as a base station 105 may include subcomponents such as anaccess network entity, which may be an example of an access nodecontroller (ANC). Each access network entity may communicate with anumber of UEs 115 through a number of other access network transmissionentities, each of which may be an example of a smart radio head, or atransmission/reception point (TRP). In some configurations, variousfunctions of each access network entity or base station 105 may bedistributed across various network devices (e.g., radio heads and accessnetwork controllers) or consolidated into a single network device (e.g.,a base station 105).

Wireless communications system 100 may operate in an ultra-highfrequency (UHF) frequency region using frequency bands from 700 MHz to2600 MHz (2.6 GHz), although in some cases, wireless local area networks(WLANs) may use frequencies as high as 4 GHz. This region may also beknown as the decimeter band, since the wavelengths range fromapproximately one decimeter to one meter in length. UHF waves maypropagate mainly by line of sight, and may be blocked by buildings andenvironmental features. However, the waves may penetrate wallssufficiently to provide service to UEs 115 located indoors. Transmissionof UHF waves is characterized by smaller antennas and shorter range(e.g., less than 100 km) compared to transmission using the smallerfrequencies (and longer waves) of the high frequency (HF) or very highfrequency (VHF) portion of the spectrum. In some cases, wirelesscommunications system 100 may also utilize extremely high frequency(EHF) portions of the spectrum (e.g., from 30 GHz to 300 GHz). Thisregion may also be known as the millimeter band, since the wavelengthsrange from approximately one millimeter to one centimeter in length.Thus, EHF antennas may be even smaller and more closely spaced than UHFantennas. In some cases, this may facilitate use of antenna arrayswithin a UE 115 (e.g., for directional beamforming). However, EHFtransmissions may be subject to even greater atmospheric attenuation andshorter range than UHF transmissions.

Wireless communications system 100 may thus support mmW communicationsbetween UEs 115 and base stations 105. Devices operating in mmW or EHFbands may have multiple antennas to allow beamforming. That is, a basestation 105 may use multiple antennas or antenna arrays to conductbeamforming operations for directional communications with a UE 115.Beamforming (which may also be referred to as spatial filtering ordirectional transmission) is a signal processing technique that may beused at a transmitter (e.g. a base station 105) to shape and/or steer anoverall antenna beam in the direction of a target receiver (e.g. a UE115). This may be achieved by combining elements in an antenna array insuch a way that transmitted signals at particular angles experienceconstructive interference while others experience destructiveinterference.

Multiple-input multiple-output (MIMO) wireless systems use atransmission scheme between a transmitter (e.g. a base station 105) anda receiver (e.g. a UE 115), where both transmitter and receiver areequipped with multiple antennas. Some portions of wirelesscommunications system 100 may use beamforming. For example, base station105 may have an antenna array with a number of rows and columns ofantenna ports that the base station 105 may use for beamforming in itscommunication with UE 115. Signals may be transmitted multiple times indifferent directions (e.g., each transmission may be beamformeddifferently). A mmW receiver (e.g., a UE 115) may try multiple beams(e.g., antenna subarrays) while receiving the synchronization signals.

In some cases, the antennas of a base station 105 or UE 115 may belocated within one or more antenna arrays (e.g., panels), which maysupport beamforming or MIMO operation. One or more base station antennasor antenna arrays may be collocated at an antenna assembly, such as anantenna tower. In some cases, antennas or antenna arrays associated witha base station 105 may be located in diverse geographic locations. Abase station 105 may use multiple antennas or antenna arrays to conductbeamforming operations for directional communications with a UE 115.

In some cases, wireless communications system 100 may be a packet-basednetwork that operate according to a layered protocol stack. In the userplane, communications at the bearer or Packet Data Convergence Protocol(PDCP) layer may be IP-based. A radio link control (RLC) layer may insome cases perform packet segmentation and reassembly to communicateover logical channels. A medium access control (MAC) layer may performpriority handling and multiplexing of logical channels into transportchannels. The MAC layer may also use hybrid automatic repeat request(HARD) to provide retransmission at the MAC layer to improve linkefficiency. In the control plane, the RRC protocol layer may provideestablishment, configuration, and maintenance of an RRC connectionbetween a UE 115 and a network device, or core network 130 supportingradio bearers for user plane data. At the physical (PHY) layer,transport channels may be mapped to physical channels.

A resource element may consist of one symbol period and one subcarrier(e.g., a 15 kHz frequency range). A resource block may contain 12consecutive subcarriers in the frequency domain and, for a normal cyclicprefix in each orthogonal frequency division multiplexed (OFDM) symbol,7 consecutive OFDM symbols in the time domain (1 slot), or 84 resourceelements. The number of bits carried by each resource element may dependon the modulation scheme (the configuration of symbols that may beselected during each symbol period). Thus, the more resource blocks thata UE 115 receives and the higher the modulation scheme, the higher thedata rate may be.

Wireless communications system 100 may support operation on multiplecells or carriers, a feature which may be referred to as carrieraggregation (CA) or multi-carrier operation. A carrier may also bereferred to as a component carrier (CC), a layer, a channel, etc. Theterms “carrier,” “component carrier,” “cell,” and “channel” may be usedinterchangeably herein. A UE 115 may be configured with multipledownlink CCs and one or more uplink CCs for carrier aggregation. Carrieraggregation may be used with both frequency division duplexed (FDD) andtime division duplexed (TDD) component carriers.

In some cases, wireless communications system 100 may utilize enhancedcomponent carriers (eCCs). An eCC may be characterized by one or morefeatures including: wider bandwidth, shorter symbol duration, shorterTTIs, and modified control channel configuration. In some cases, an eCCmay be associated with a carrier aggregation configuration or a dualconnectivity configuration (e.g., when multiple serving cells have asuboptimal or non-ideal backhaul link). An eCC may also be configuredfor use in unlicensed spectrum or shared spectrum (where more than oneoperator is allowed to use the spectrum). An eCC characterized by widebandwidth may include one or more segments that may be utilized by UEs115 that are not capable of monitoring the whole bandwidth or prefer touse a limited bandwidth (e.g., to conserve power).

A shared radio frequency spectrum band may be utilized in an NR sharedspectrum system. For example, an NR shared spectrum may utilize anycombination of licensed, shared, and unlicensed spectrums, among others.The flexibility of eCC symbol duration and subcarrier spacing may allowfor the use of eCC across multiple spectrums. In some examples, NRshared spectrum may increase spectrum utilization and spectralefficiency, specifically through dynamic vertical (e.g., acrossfrequency) and horizontal (e.g., across time) sharing of resources.

In some cases, wireless communications system 100 may utilize bothlicensed and unlicensed radio frequency spectrum bands. For example,wireless communications system 100 may employ LTE License AssistedAccess (LTE-LAA) or LTE Unlicensed (LTE U) radio access technology or NRtechnology in an unlicensed band such as the 5 GHz Industrial,Scientific, and Medical (ISM) band. When operating in unlicensed radiofrequency spectrum bands, wireless devices such as base stations 105 andUEs 115 may employ listen-before-talk (LBT) procedures to ensure thechannel is clear before transmitting data. In some cases, operations inunlicensed bands may be based on a CA configuration in conjunction withCCs operating in a licensed band. Operations in unlicensed spectrum mayinclude downlink transmissions, uplink transmissions, or both. Duplexingin unlicensed spectrum may be based on FDD, TDD or a combination ofboth.

In wireless communications system 100, resources (e.g., uplinkresources) may be allocated for the transmission of beam recoverymessages. For example, a UE 115 communicating in wireless communicationssystem 100 may receive a configuration for resources from a base station105, where the resources may be dedicated for beam recovery signaling.The UE 115 may identify a beam failure (e.g., due to path loss orinterference) on one or more active beams used to communicate with thebase station 105, and the UE 115 may transmit a beam recovery message tothe base station 105. In such cases, the beam recovery message may betransmitted according to the configuration received from the basestation 105 such that the beam recovery message is transmitted using thededicated beam recovery resources. In some cases, the configuration maybe received at the UE 115 via RRC signaling or via a system informationbroadcast from the base station 105. Additionally, the use of the beamrecovery resources may be enabled or disabled by an indication from thebase station 105 (e.g., using layer 1 (L1) (i.e., PHY layer) signalingor layer 2 (L2) signaling), where the UE 115 may transmit the beamrecovery message on different sets of resources based on whether thebeam recovery resources are enabled or disabled.

FIG. 2 illustrates an example of a wireless communications system 200that supports uplink resources for beam recovery in accordance withvarious aspects of the present disclosure. Wireless communicationssystem 200 includes a base station 105-a and a UE 115-a, each of whichmay be an example of the corresponding devices as described withreference to FIG. 1. Wireless communications system 200 may support theuse of dedicated resources (e.g., time, frequency, and/or spatialresources) for the transmission of a beam recovery message.

Wireless communications system 200 may operate in frequency ranges thatare associated with beamformed transmissions between base station 105-aand UE 115-a. For example, wireless communications system 200 mayoperate using mmW frequency ranges. As a result, signal processingtechniques, such as beamforming, may be used to coherently combineenergy and overcome path losses. By way of example, base station 105-amay contain multiple antennas. Each antenna may transmit (or receive) aphase-shifted version of a signal such that the phase-shifted versionsconstructively interfere in certain regions and destructively interferein others. Weights may be applied to the various phase-shifted versionsof the signal, e.g., to steer the transmissions in a desired direction.Such techniques (or similar techniques) may serve to increase thecoverage area 110-a of the base station 105-a or otherwise benefitwireless communications system 200.

Transmit beams 205-a and 205-b represent examples of beams over whichdata (e.g., or control information) may be transmitted. Accordingly,each transmit beam 205 may be directed from base station 105-a toward adifferent region of the coverage area 110-a, and in some cases, two ormore beams may overlap. Transmit beams 205-a and 205-b may betransmitted simultaneously or at different times. In either case, a UE115-a may be capable of receiving the information sent using one or moretransmit beams 205 via respective receive beams 210.

In one example, UE 115-a may include multiple antennas and form one ormore receive beams 210 (e.g., receive beams 210-a and 210-b). Thereceive beams 210-a, 210-b may each receive one of the transmit beams205-a and 205-b (e.g., UE 115-a may be positioned within wirelesscommunications system 200 such that UE 115-a receives both beamformedtransmit beams 205). Such a scheme may be referred to as areceive-diversity scheme. In some cases, the receive beams 210 may eachreceive a single transmit beam 205 (e.g., receive beam 210-a may receivethe transmit beam 205-a with various path loss and multipath effectsincluded). That is, each antenna of UE 115-a may receive the transmitbeam 205-a which has experienced different path losses or phase shifts(e.g., different phase shifts may be due to the different path lengthsbetween the base station 105-a and the respective antennas of the UE115-a) and appropriately combine the received signals in one or morereceive beams 210. In other examples, a single receive beam 210 mayreceive multiple transmit beams 205.

A transmit beam 205 and a corresponding receive beam 210 may be referredto as a beam pair. The beam pair may be established during cellacquisition (e.g., through synchronization signals) or through a beamrefinement procedure where the UE 115-a and base station 105-a tryvarious combinations of finer transmission beams and receive beams untila suitable beam pair is determined. Although the above examples aredescribed in terms of downlink transmissions, the same concepts may beextended to uplink transmissions in accordance with aspects of thepresent disclosure. That is, the receive beams 210 illustrated in FIG. 2may alternatively represent transmit beams for uplink signals from UE115-a, and base station 105-a may receive the uplink signals using oneor more receive beams. In some cases, each beam pair may be associatedwith a signal quality (e.g., such that UE 115-a and base station 105-amay preferentially communicate over a beam pair with a better signalquality).

As described above, a significant challenge in some wireless systems(e.g., mmW systems) is that of high path loss. Accordingly, techniques(e.g., hybrid beamforming), which may not be present in legacy systems(e.g., 3G and 4G systems), may be utilized to overcome path loss andimprove communications efficiency. For example, hybrid beamforming maypermit multi-beam operation to users, which may enhance the link budget(e.g., resource efficiency) and SNR within wireless communicationssystem 200.

In some cases, base station 105-a and UE 115-a may communicate over oneor more active beam pairs, as described above. Each beam pair may carryone or more channels. Examples of such channels include a physicaldownlink shared channel (PDSCH), a physical downlink control channel(PDCCH), a physical uplink shared channel (PUSCH), and a physical uplinkcontrol channel (PUCCH).

In multi-beam operation, one or more active beam pairs may becomemisaligned (e.g., which may be referred to herein as a beam failure).This misalignment may be the result of beam switch failure, signalblockage, etc. In such a scenario, base station 105-a and UE 115-a maynot be able to communicate (e.g., data or control information) over themisaligned active beams.

In some cases, UE 115-a may detect the beam failure by monitoring asubset of reference beams or signals, such as synchronization signals orreference signals. For example, these signals may include asynchronization signal (e.g., an NR synchronization signal (NR-SS) thatincludes a primary synchronization signal (PSS) and a secondarysynchronization signal (SSS)) and one or more reference signals (e.g., amobility reference signal (MRS)). In other examples, these signals mayinclude a synchronization signal block (SS block) that includes, forexample, the PSS, the SSS, and/or a physical broadcast channel (PBCH).In some cases, these signals may be multiplexed (e.g., time or frequencymultiplexed) in the same region of a resource grid. In some cases, oneor more of the reference signals may be transmitted using multi-porttransmission (e.g., a given analog beam may comprise up to an eight-portdigital transmission). Upon detection of a beam failure (e.g., which mayalso be referred to as a link failure), UE 115-a may attempt to accessuplink resources to reconnect with the serving cell (e.g., by sendinginformation for reestablishment of a beam pair). In aspects of themulti-beam operation described herein, uplink resources may beconfigured so that base station 105-a may create a receive beam in thosedirections from which the UE(s) 115 are transmitting.

In some systems, SR resources may be multiplexed (e.g., time orfrequency multiplexed) with RACH resources such that the sets ofresources may overlap in time but occupy different resource blocks. TheSR resources and RACH resources may be included in a control region,which may alternatively be referred to as a RACH. In some systems, theNR-SS for a given active beam may be mapped to resources in the RACHregion (e.g., such that the NR-SS of each beam is mapped to separateresources in the RACH region). Accordingly, SR resources (e.g., or RACHresources) in the control region of a resource grid may be used toconvey the beam recovery request.

However, such an implementation may have drawbacks. As an example, theRACH region may carry a limited amount of information (e.g., because theRACH and SR share resources). Additionally or alternatively, using RACHor SR resources for beam recovery may be associated with relatively highlatency (e.g., because these resources may be available infrequently),resulting in relatively long periods of time (e.g., on the order of 100ms) before UE 115-a is able to send the beam recovery information.Further, because the RACH resources may be contention-based, UE 115-amay not be able to access these periodically allocated resources.Because of the limited capacity of the resources in the control region,the information contained in the beam recovery request may also belimited. Accordingly, in some systems, UE 115-a may be allocated (e.g.,additional) resources over which beam recovery information iscommunicated to base station 105-a.

In aspects of the present disclosure, base station 105-a may configurededicated resources (e.g., resource elements (REs)) to one or more UEs115 such that beam recovery may not be restricted to the NR-SSassociated resources in the control region. In some cases, theconfiguration may be sent using RRC signaling, or may be sent using asystem information broadcast. The configuration may be enabled anddisabled using L1/L2 signaling. That is, UE 115-a may in some cases betriggered to access additional resources for the beam recovery process(e.g., through a resource grant from base station 105-a). Accordingly,the resources used for beam recovery may be contention-free, and UE115-a may access the dedicated resources once triggered (or granted) bybase station 105-a. Additionally or alternatively, the configuration maybe specific to a UE 115 (or a group of UEs 115). In some cases, theconfiguration may be traffic dependent. For example, e.g. to reduce beamrecovery delay, base station 105-a may configure a set of UEs 115 withuplink resources that occur more frequently in time. Alternatively, in alow-traffic scenario (e.g., when UE 115-a has a relatively small amountof data to transmit), the SR resources in the RACH region may suffice(e.g., because delays may be more tolerable in such a scenario). In someaspects, base station 105-a may configure UEs 115 that have a high SNRto use any beam on the uplink for beam recovery.

In some cases, base station 105-a may specify a SFN, periodicity, REs, aslot or mini-slot, an SFI, etc. for the uplink resources. As an example,the number of REs configured per uplink beam may vary depending on thenumber of UEs 115 that are using the beam. Accordingly, base station105-a may specify a total number of beam recovery requests to be made byUE 115-a, which may be based on the number of configured REs or based onother conditions (e.g., a timer). In some cases, base station 105-a mayconfigure more frequency or time resources in certain beams (e.g., for alarger payload) than in other beams. Additionally, the configuredresources may be in a region other than the RACH region.

Base station 105-a may specify a relationship between downlink beams anduplink resources. That is, base station 105-a may provide equivalentuplink resources for each downlink beam. In some cases, the downlinkbeams may be based on, for example, one or more of an NR-SS, an MRS, ora CSI-RS (e.g., a periodic CSI-RS). In aspects of the presentdisclosure, respective reference signals may be associated with its owndedicated uplink resources. The periodicity of the dedicated uplinkresources may be based on the periodicity of the associated referencesignal. That is, the periodicity of the uplink resources may be greaterthan, equal to, or less than the periodicity of associated referencesignals. By way of example, the periodicity of the uplink resources maybe a multiple (e.g., an integer multiple) of the associated referencesignal. Different relationships between the periodicities of referencesignals and uplink resources not stated herein are also contemplated,including those based on a relationship or a correlation between theuplink resources and one or more reference signals. In some cases, themeasurement reference signals (e.g., MRS and CSI-RS) may be transmittedmore frequently than the NR-SS.

UE 115-a may determine beam failure on one or more active beams and usethe configured resources to send a beam recovery message. For example,UE 115-a may monitor a set of reference signals to determine whether abeam failure has occurred (e.g., whether a beam failure condition hasbeen met), and transmit the beam recovery message based on adetermination that an active beam has failed. The beam recovery messagemay be sent over one or more uplink resources and/or in one or more beamdirections. The beam recovery message may contain measurements ofreference signals from one or more beams or one or more cells. In somecases, these measurements may be performed before and/or after beamfailure is detected. That is, in some cases, the periodicity of thededicated uplink resources may be lower than the periodicity of thereference signals such that UE 115-a may continue measuring referencesignals while waiting for the dedicated uplink resources. The referencesignals may include NR-SS, MRS, and CSI-RS. Measurement results mayinclude an indication of RSRP, RSRQ, CQI, PMI, rank indicator (RI), andthe like. In some cases, UE 115-a may also provide direction information(e.g., a mobility condition including a direction of UE 115-a, adistance from base station 105-a, an orientation of UE 115-a, etc.)and/or UE panel information (e.g., a number of antennas or antennaarrays at UE 115-a).

In some cases, UE 115-a may specify a downlink beam identifier (e.g.,explicitly and/or implicitly by using the appropriately mapped uplinkresources for the given downlink beam). For instance, UE 115-a mayidentify, within the beam recovery message, one or more candidate beams(e.g., using a beam identifier) that may be used for beam recovery. Insuch cases, the beam recovery message may further include informationregarding a signal quality of the candidate beam(s) (e.g., based on themeasurements of reference signals on the candidate beams). In otherexamples, UE 115-a may send information in the beam recovery requestthat indicates whether a candidate beam exists based on the performedmeasurements.

Base station 105-a may receive one or more beam recovery messages fromUE 115-a. Because the identity of UE 115-a may be known to base station105-a, base station 105-a may respond to a subset of the beam recoverymessages. That is, in some cases, multiple UEs 115 may transmitsimultaneously over the same resources, and base station 105-a maydistinguish the transmissions based on a scrambling code (e.g., whichmay be based on a cell radio network temporary identifier (C-RNTI) forRRC-connected UEs 115). In some cases, base station 105-a may respondwith a confirmation of a candidate beam indicated by UE 115-a, or maysignal a different beam for beam recovery. The beam chosen by basestation 105-a may rely on the measurement report received in the beamrecovery message. For example, base station 105-a may choose to useanother beam (e.g., a refined beam) if the measurement report messagesuggests that UE 115-a can use the same receive beam to receive theother beam (e.g., the refined beam). In some cases, a transmit beamchosen by base station 105-a may rely on uplink measurements performedat base station 105-a. The PDCCH transmitted to UE 115-a may indicatethe presence of additional reference signal(s) for beam refinement. Inother examples, a beam may not be available for beam recovery.

FIG. 3 illustrates an example of a resource grid 300 in a system thatsupports dedicated uplink resources for beam recovery in accordance withvarious aspects of the present disclosure. The resource grid 300 may,for example, be used by a UE 115 as described with reference to FIGS. 1and 2. Resource grid 300 may be associated with a given beam pairbetween a serving base station 105 (not shown) and UE 115-b. Aspects ofresource grid 300 have been simplified for the sake of explanation.Accordingly, the arrangement and periodicity of the various resourcesdescribed below may vary from what is depicted in FIG. 3.

Resource grid 300 may include a first subset of resources 305-a and asecond subset of resources 305-b within a system bandwidth. The firstand second subset of resources 305-a may correspond to multiplesubcarriers 310 transmitted over a number of symbol periods 315 (e.g.,OFDM symbols). A block spanning one symbol period 315 and one subcarrier310 may be referred to as an RE. Alternatively, each block may span agroup of subcarriers 310 (e.g., 12 subcarriers) and one subframe (e.g.,a TTI), such that each block may be referred to as a resource block(RB). Accordingly, the units of frequency and time used in the presentexample may be arbitrary such that they are used for the sake ofexplanation only. The first subset of resources 305-a may be an exampleof control resources (i.e., resources over which control channelinformation may be transmitted). As an example, the first subset ofresources 305-a may carry PUCCH and physical RACH (PRACH) transmissionsfrom one or more UEs 115. In some examples, the PUCCH and/or PRACHtransmissions may include the transmission of the beam recovery messageusing these channels. Additionally, the first subset of resources 305-amay contain RACH resources 325 and SR resources 320. In some cases, theRACH resources 325 and SR resources 320 may be multiplexed such thatthey may overlap in time or frequency (e.g., occupy the same symbolperiod 315 or subcarrier 310) but occupy different REs (e.g., do notoverlap in both time and frequency).

The second subset of resources 305-b may be an example of resources in adata region of the system bandwidth. In aspects, the bandwidth of thesecond subset of resources 305-b may be wider than that of the firstsubset of resources 305-a. In some examples, resources 305-b may be usedto carry PUSCH transmissions.

In some cases, UE 115-b may be able to communicate with a serving basestation 105 over more than one active beam (e.g., active beams 330 and335 in the present example). Each active beam may have an associatedsignal quality, and, in some cases, UE 115-b may preferentiallycommunicate with the serving base station 105 over a stronger beam(e.g., active beam 330 having relatively higher SNR compared to anotheractive beam(s)). Each active beam 330, 335 may be an example of adownlink receive beam, as described with reference to FIG. 2.Accordingly, each active beam 330, 335 may be used to receive one ormore reference signals (e.g., NR-SS, MRS, CSI-RS, etc.) from the basestation 105. UE 115-b may monitor these reference signals in therespective active beams 330, 335 (e.g., to detect a beam failure).

In some examples, active beam 330 may experience a beam failure (e.g.,because of signal blockage, movement of UE 115-b, etc.). Accordingly, UE115-b may fail to receive one or more reference signals of the activebeam 330. In some cases, the UE 115-b may attempt to report the beamfailure to the serving base station 105 using SR resources 320 and/orRACH resources 325. That is, each active beam 330, 335 may have anassociated set of SR resources 320 and/or RACH resources 325 over whichbeam recovery information may be transmitted. However, SR resources 320and RACH resources 325 may occur relatively infrequently within resourcegrid 300. Further, these resources may be examples of contention-basedresources, such that UE 115-b may not be able to access them even whenthey do occur.

Thus, in some cases, a base station 105 may additionally oralternatively configure dedicated resources within the second subset ofresources 305-b to be used to convey beam recovery information. In somecases, the dedicated resources may be mapped to specific referencesignals and/or to specific active beams 330, 335. For example, activebeam 330 may carry one or more of NR-SS, MRS, and CSI-RS. Each of thesereference signals may have a dedicated set of resources over which beamfailure information may be conveyed. Alternatively, one or more of thesereference signals may share resources. As an example, UE 115-b may beconfigured to report NR-SS failure of active beam 330 using SR resources320, MRS failure of active beam 330 using dedicated uplink resources340-a, and CSI-RS failure of active beam 330 using dedicated uplinkresources 340-b. Other mappings of reference signals for downlink activebeam 330 may be possible. In some cases, an MRS and/or CSI-RS may betransmitted more frequently than an NR-SS. In some cases, dedicateduplink resources 340 may occur less frequently than the associatedreference signals.

Additionally or alternatively, different sets of resources may bereserved for beam failure recovery requests for different beams. Forinstance, one or more sets of dedicated uplink resources 345 may bereserved to transmit beam recovery information for active beam 335 inaddition to dedicated uplink resources 340 for active beam 330. In somecases, the dedicated uplink resources 340 and 345 may occur over thesame resource blocks, but be differentiated because the active beams 330and 335 may cover different directions. Such frequency reuse may not bepossible in RACH resources 325 (e.g., because RACH resources 325 may bebroadly allocated in all directions). In some cases, multiple UEs 115may transmit in a given set of dedicated uplink resources 340, 345. EachUE 115 may be associated with a different C-RNTI such that each UE 115may scramble transmissions over the dedicated uplink resources 340, 345in accordance with respective C-RNTIs. Such multiplexing may not bepossible with RACH resources 325 in which UEs 115 may use one or morecommon identifiers.

In some cases, the dedicated uplink resources 340, 345 may be configuredto occur more frequently than the RACH resources 325 or the SR resources320. Additionally or alternatively, the dedicated uplink resources 340,345 may support higher data rates (e.g., have a wider bandwidth, longerduration, support higher modulation and coding schemes (MCS), etc.) thanthe RACH resources 325 or the SR resources 320. Accordingly thededicated uplink resources 340, 345 may be able to carry additional beamrecovery information, as described above with reference to FIG. 2. Insome examples, the additional information carried in dedicated uplinkresources 340, 345 may include an SR transmitted to the base station 105(e.g., included in the beam recover request message).

In some cases, UE 115-b may default to attempting to transmit a beamrecovery message over the SR resources 320. In some examples, UE 115-bmay not be able to access the SR resources 320 and may subsequentlyattempt to access RACH resources 325. UE 115-b may receive aconfiguration (e.g., via RRC signaling) specifying which resources arededicated for transmission of beam recovery message (e.g., which time,frequency, and beam resources may be used), and UE 115-b mayautonomously decide to access the dedicated uplink resources 340, 345.Additionally or alternatively, UE 115-b may be triggered (e.g., viaL1/L2 signaling) to use these dedicated uplink resources 340, 345.

FIG. 4 illustrates an example of a process flow 400 in a system thatsupports uplink resources for beam recovery in accordance with variousaspects of the present disclosure. Process flow 400 includes a UE 115-cand base station 105-b, each of which may be an example of thecorresponding devices described above with reference to FIGS. 1 through3. Process flow 400 may illustrate an example of the signaling ofdedicated uplink resources used for the transmission of a beam recoverymessage.

At 405, UE 115-c and base station 105-b may establish a communicationusing one or more active beams. At 410, base station 105-b may identifya communication parameter associated with one or more active beams overwhich base station 105-b is communicating with UE 115-c. In some cases,the base station 105-b may identify a traffic level associated with UE115-c (e.g., or a group of UEs 115). Additionally or alternatively, basestation 105-b may identify an SNR associated with the communication withUE 115-c established at 405. In some cases, base station 105-b mayidentify a payload associated with an uplink transmission from UE 115-c.

At 415, the base station 105-b may transmit (e.g., and UE 115-c mayreceive) a configuration for uplink beam recovery resources. In somecases, the uplink beam recovery resources are associated with a firstregion of resources that are different from a second region of resourcesallocated for transmission of a random access message (e.g., for RACHmessages). In some cases, base station 105-b may transmit theconfiguration as part of RRC signaling. Additionally or alternatively,the configuration may be transmitted using a system informationbroadcast.

Accordingly, UE 115-c may receive the configuration as part of RRCsignaling or as part of the system information broadcast from basestation 105-b. In some examples, the configuration of the uplinkresources depends on one or more of the communication parametersdetermined at 410. For example, the uplink resource configuration may bebased on the identified traffic level and be transmitted to one or moreUEs 115. Additionally or alternatively, the uplink resourceconfiguration may be specific to UE 115-c based on the SNR associatedwith UE 115-c. In some aspects, the configuration may include anindication of additional beam recovery resources allocated for one ormore beam recovery messages based at least on the identified payload. Insome cases, the configuration may include an indication of a set ofbeams for each of one or more beam recovery messages.

In some cases, base station 105-b may identify one or more referencesignals associated with a set of downlink beams and may identify amapping between uplink beam recovery resources and the set of downlinkbeams based on the reference signals. Base station 105-b may include anindication of the mapping as part of the configuration at 415. In somecases, the configuration includes an indication of an SFN correspondingto the uplink beam recovery resources, an SFI corresponding to theuplink beam recovery resources, a periodicity corresponding to theuplink beam recovery resources, one or more REs corresponding to theuplink beam recovery resources, or a combination thereof

At 420, base station 105-b may optionally enable or disable the use ofthe uplink beam recovery resources for the transmission of the beamrecovery message. In some cases, the indication that enables or disablesthe use of the resources may be sent using L1/L2 signaling. At 425, UE115-c may identify a beam failure of one or more active beams used forthe communication established at 405.

At 430, UE 115-c may optionally perform measurements of various signalsreceived from base station 105-b. In some cases, these measurements maybe performed before and/or after the beam failure is identified at 425.In some cases, UE 115-c may perform measurements of a set of referencesignals. The set of reference signals may be associated with the one ormore active beams established at 405. In some cases, the set ofreference signals includes a synchronization signal, a MRS, a CSI-RS, ora combination thereof. In some cases, UE 115-c may determine a mobilitycondition associated with UE 115-c, the mobility condition of UE 115-cincluding a direction of UE 115-c relative to base station 105-b, anorientation of UE 115-c, a distance to base station 105-b, or acombination thereof. In some cases, UE 115-c may identify antenna arrayinformation corresponding to one or more antenna arrays located at UE115-c. In some cases, the antenna array information includes a number ofantenna arrays located at UE 115-c.

At 435, UE 115-c may transmit (e.g., and base station 105-b may receive)a beam recovery message according to the received configuration usingthe uplink beam recovery resources based on the beam failure identifiedat 425. The beam recovery message may comprise a transmission of a beamfailure recovery request. In some cases, base station 105-b may receiveone or more beam recovery messages on a set of resources in one or morereceive beam directions. In some cases, UE 115-c may transmit the beamrecovery message on one or more resources in one or more beamdirections. In aspects, the beam recovery message may be transmittedusing at least one of the plurality of beams indicated in theconfiguration at 415 (e.g., based on an SNR associated with UE 115-c).In some examples, UE 115-c may transmit, according to the configurationreceived at 415, an SR to base station 105-b using the uplink beamrecovery resources. In some cases, UE 115-c may transmit the beamrecovery message based on the indication at 420 that enables or disablesthe use of the uplink beam resources for transmission of the beamrecovery message.

In some examples, the beam recovery message may include a measurementreport based on the measurements performed at 430. The measurementreport may include, for example, an RSRP, RSRQ, CQI, PMI, a rank (e.g.,an RI), or a combination thereof. Additionally or alternatively, thebeam recovery message may include an indication of the mobilitycondition determined at 430. The beam recovery message may, in somecases, include an indication of the antenna array information determinedat 430. In some examples, UE 115-c may determine an identity of one ormore downlink beams from base station 105-b and include an indication ofthe identity as part of the beam recovery message.

At 440, base station 105-b may determine a transmit beam direction basedon the measurement report included in the beam recovery message receivedat 435. In some cases, base station 105-b may perform a measurement onuplink signals over the one or more active beams and determine thetransmit beam direction based on the measurement of the uplink signals.At 445, base station 105-b may transmit (e.g., and UE 115-c may receive)a message in response to the transmitted beam recovery message, themessage including an indication of one or more reference signals forbeam refinement. In some cases, this message may be transmitted to UE115-c using the transmit beam direction determined at 440.

FIG. 5 shows a block diagram 500 of a wireless device 505 that supportsuplink resources for beam recovery in accordance with various aspects ofthe present disclosure. Wireless device 505 may be an example of aspectsof a UE 115 as described with reference to FIG. 1. wireless device 505may include receiver 510, UE beam recovery manager 515, and transmitter520. wireless device 505 may also include a processor. Each of thesecomponents may be in communication with one another (e.g., via one ormore buses).

Receiver 510 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to uplinkresources for beam recovery, etc.). Information may be passed on toother components of the device. The receiver 510 may be an example ofaspects of the transceiver 835 described with reference to FIG. 8.

UE beam recovery manager 515 may be an example of aspects of the UE beamrecovery manager 815 described with reference to FIG. 8. UE beamrecovery manager 515 and/or at least some of its various subcomponentsmay be implemented in hardware, software executed by a processor,firmware, or any combination thereof If implemented in software executedby a processor, the functions of the UE beam recovery manager 515 and/orat least some of its various subcomponents may be executed by ageneral-purpose processor, a digital signal processor (DSP), anapplication-specific integrated circuit (ASIC), an field-programmablegate array (FPGA) or other programmable logic device, discrete gate ortransistor logic, discrete hardware components, or any combinationthereof designed to perform the functions described in the presentdisclosure.

The UE beam recovery manager 515 and/or at least some of its varioussubcomponents may be physically located at various positions, includingbeing distributed such that portions of functions are implemented atdifferent physical locations by one or more physical devices. In someexamples, UE beam recovery manager 515 and/or at least some of itsvarious subcomponents may be a separate and distinct component inaccordance with various aspects of the present disclosure. In otherexamples, UE beam recovery manager 515 and/or at least some of itsvarious subcomponents may be combined with one or more other hardwarecomponents, including but not limited to an I/O component, atransceiver, a network server, another computing device, one or moreother components described in the present disclosure, or a combinationthereof in accordance with various aspects of the present disclosure.

UE beam recovery manager 515 may receive a configuration for beamrecovery resources, identify a beam failure of one or more active beamsused to communicate with a base station 105, and transmit, according tothe received configuration, a beam recovery message to the base station105 using the beam recovery resources based on the identified beamfailure.

Transmitter 520 may transmit signals generated by other components ofthe device. In some examples, the transmitter 520 may be collocated witha receiver 510 in a transceiver module. For example, the transmitter 520may be an example of aspects of the transceiver 835 described withreference to FIG. 8. The transmitter 520 may include a single antenna,or it may include a set of antennas.

FIG. 6 shows a block diagram 600 of a wireless device 605 that supportsuplink resources for beam recovery in accordance with various aspects ofthe present disclosure. Wireless device 605 may be an example of aspectsof a wireless device 505 or a UE 115 as described with reference toFIGS. 1 and 5. wireless device 605 may include receiver 610, UE beamrecovery manager 615, and transmitter 620. wireless device 605 may alsoinclude a processor. Each of these components may be in communicationwith one another (e.g., via one or more buses).

Receiver 610 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to uplinkresources for beam recovery, etc.). Information may be passed on toother components of the device. The receiver 610 may be an example ofaspects of the transceiver 835 described with reference to FIG. 8.

UE beam recovery manager 615 may be an example of aspects of the UE beamrecovery manager 815 described with reference to FIG. 8. UE beamrecovery manager 615 and/or at least some of its various subcomponentsmay be implemented in hardware, software executed by a processor,firmware, or any combination thereof If implemented in software executedby a processor, the functions of the UE beam recovery manager 615 and/orat least some of its various subcomponents may be executed by ageneral-purpose processor, a digital signal processor (DSP), anapplication-specific integrated circuit (ASIC), an field-programmablegate array (FPGA) or other programmable logic device, discrete gate ortransistor logic, discrete hardware components, or any combinationthereof designed to perform the functions described in the presentdisclosure.

The UE beam recovery manager 615 and/or at least some of its varioussubcomponents may be physically located at various positions, includingbeing distributed such that portions of functions are implemented atdifferent physical locations by one or more physical devices. In someexamples, UE beam recovery manager 615 and/or at least some of itsvarious subcomponents may be a separate and distinct component inaccordance with various aspects of the present disclosure. In otherexamples, UE beam recovery manager 615 and/or at least some of itsvarious subcomponents may be combined with one or more other hardwarecomponents, including but not limited to an I/O component, atransceiver, a network server, another computing device, one or moreother components described in the present disclosure, or a combinationthereof in accordance with various aspects of the present disclosure. UEbeam recovery manager 615 may also include resource configurationcomponent 625, beam failure component 630, and UE beam recovery messagemanager 635.

Resource configuration component 625 may receive a configuration forbeam recovery resources. In some cases, receiving the configuration forthe beam recovery resources includes receiving the configuration as partof RRC signaling from a base station 105, or as part of a systeminformation broadcast from the base station 105. In some examples, theconfiguration may include a UE-specific configuration for beam recoveryresources. In some cases, the configuration includes an indication of aset of beams for transmitting a beam recovery message, where theindication may be based on an SNR associated with the UE 115. In somecases, the configuration may include an indication of an SFNcorresponding to the beam recovery resources, an SFI corresponding tothe beam recovery resources, a periodicity corresponding to the beamrecovery resources, one or more REs corresponding to the beam recoveryresources, or a combination thereof. In some cases, the beam recoveryresources may occupy a first region of resources that is different froma second region of resources allocated for transmission of a randomaccess message (e.g., a RACH). In some cases, the configuration mayinclude an indication of a mapping between a downlink beam from the basestation 105 and the beam recovery resources.

Beam failure component 630 may identify a beam failure of one or moreactive beams used to communicate with a base station 105. UE beamrecovery message manager 635 may transmit, according to the receivedconfiguration, a beam recovery message to the base station 105 using thebeam recovery resources and based on the identified beam failure. Insome cases, UE beam recovery message manager 635 may receive anindication that enables the use of the beam recovery resources for thetransmission of the beam recovery message, where transmitting the beamrecovery message is based on the indication. Additionally oralternatively, UE beam recovery message manager 635 may receive anindication that disables the use of the beam recovery resources for thetransmission of the beam recovery message. In some examples,transmitting the beam recovery message to the base station 105 mayinclude transmitting the beam recovery message using at least one of theset of beams indicated by the base station 105. In some cases,transmitting the beam recovery message to the base station 105 includestransmitting the beam recovery message on one or more resources in oneor more beam directions.

Transmitter 620 may transmit signals generated by other components ofthe device. In some examples, the transmitter 620 may be collocated witha receiver 610 in a transceiver module. For example, the transmitter 620may be an example of aspects of the transceiver 835 described withreference to FIG. 8. The transmitter 620 may include a single antenna,or it may include a set of antennas.

FIG. 7 shows a block diagram 700 of a UE beam recovery manager 715 thatsupports uplink resources for beam recovery in accordance with variousaspects of the present disclosure. The UE beam recovery manager 715 maybe an example of aspects of a UE beam recovery manager 515, a UE beamrecovery manager 615, or a UE beam recovery manager 815 described withreference to FIGS. 5, 6, and 8. UE beam recovery manager 715 and/or atleast some of its various subcomponents may be implemented in hardware,software executed by a processor, firmware, or any combination thereofIf implemented in software executed by a processor, the functions of theUE beam recovery manager 715 and/or at least some of its varioussubcomponents may be executed by a general-purpose processor, a digitalsignal processor (DSP), an application-specific integrated circuit(ASIC), an field-programmable gate array (FPGA) or other programmablelogic device, discrete gate or transistor logic, discrete hardwarecomponents, or any combination thereof designed to perform the functionsdescribed in the present disclosure.

The UE beam recovery manager 715 and/or at least some of its varioussubcomponents may be physically located at various positions, includingbeing distributed such that portions of functions are implemented atdifferent physical locations by one or more physical devices. In someexamples, UE beam recovery manager 715 and/or at least some of itsvarious subcomponents may be a separate and distinct component inaccordance with various aspects of the present disclosure. In otherexamples, UE beam recovery manager 715 and/or at least some of itsvarious subcomponents may be combined with one or more other hardwarecomponents, including but not limited to an I/O component, atransceiver, a network server, another computing device, one or moreother components described in the present disclosure, or a combinationthereof in accordance with various aspects of the present disclosure.The UE beam recovery manager 715 may include resource configurationcomponent 720, beam failure component 725, UE beam recovery messagemanager 730, beam refinement component 735, scheduling request component740, signal measurement component 745, mobility condition component 750,antenna information component 755, and downlink beam component 760. Eachof these modules may communicate, directly or indirectly, with oneanother (e.g., via one or more buses).

Resource configuration component 720 may receive a configuration forbeam recovery resources. In some cases, receiving the configuration forthe beam recovery resources includes receiving the configuration as partof RRC signaling from a base station 105, or as part of a systeminformation broadcast from the base station 105. In some examples, theconfiguration may include a UE-specific configuration for beam recoveryresources. In some cases, the configuration includes an indication of aset of beams for transmitting a beam recovery message, where theindication may be based on an SNR associated with the UE 115. In somecases, the configuration may include an indication of an SFNcorresponding to the beam recovery resources, an SFI corresponding tothe beam recovery resources, a periodicity corresponding to the beamrecovery resources, one or more REs corresponding to the beam recoveryresources, or a combination thereof. In some cases, the beam recoveryresources may occupy a first region of resources that is different froma second region of resources allocated for transmission of a randomaccess message (e.g., a RACH). In some cases, the configuration mayinclude an indication of a mapping between a downlink beam from the basestation 105 and the beam recovery resources.

Beam failure component 725 may identify a beam failure of one or moreactive beams used to communicate with a base station 105. UE beamrecovery message manager 730 may transmit, according to the receivedconfiguration, a beam recovery message to the base station 105 using thebeam recovery resources and based on the identified beam failure. Insome cases, UE beam recovery message manager 730 may receive anindication that enables the use of the beam recovery resources for thetransmission of the beam recovery message, where transmitting the beamrecovery message is based on the indication. Additionally oralternatively, UE beam recovery message manager 730 may receive anindication that disables the use of the beam recovery resources for thetransmission of the beam recovery message. In some examples,transmitting the beam recovery message to the base station 105 mayinclude transmitting the beam recovery message using at least one of theset of beams indicated by the base station 105. In some cases,transmitting the beam recovery message to the base station 105 includestransmitting the beam recovery message on one or more resources in oneor more beam directions.

Beam refinement component 735 may receive a message from the basestation 105 in response to the transmitted beam recovery message, themessage including an indication of a set of reference signals for beamrefinement. Scheduling request component 740 may transmit, according tothe received configuration, an SR to the base station 105 using the beamrecovery resources. Signal measurement component 745 may performmeasurements of a set of reference signals, the set of reference signalsassociated with the one or more active beams. In such cases, the beamrecovery message may include a measurement report based on the performedmeasurements. In some cases, the measurement report includes an RSRP, anRSRQ, a CQI, a PMI, a rank, or a combination thereof In some cases, theset of reference signals includes a synchronization signal, a mobilityreference signal, a CSI-RS, or a combination thereof.

Mobility condition component 750 may determine a mobility conditionassociated with the UE 115, the mobility condition of the UE 115including a direction of the UE 115 relative to the base station 105, anorientation of the UE 115, a distance from the base station 105, or acombination thereof. In such cases, the beam recovery message mayinclude an indication of the mobility condition. Antenna informationcomponent 755 may identify antenna array information corresponding toone or more antenna arrays located at the UE 115, where the beamrecovery message includes an indication of the antenna arrayinformation. In some cases, the antenna array information includes anumber of antenna arrays located at the UE 115. Downlink beam component760 may determine an identity of a downlink beam from the base station105, where the beam recovery message includes an indication of theidentity of the downlink beam.

FIG. 8 shows a diagram of a system 800 including a device 805 thatsupports uplink resources for beam recovery in accordance with variousaspects of the present disclosure. Device 805 may be an example of orinclude the components of wireless device 505, wireless device 605, or aUE 115 as described above, e.g., with reference to FIGS. 1, 5 and 6.Device 805 may include components for bi-directional voice and datacommunications including components for transmitting and receivingcommunications, including UE beam recovery manager 815, processor 820,memory 825, software 830, transceiver 835, antenna 840, and I/Ocontroller 845. These components may be in electronic communication viaone or more busses (e.g., bus 810). Device 805 may communicatewirelessly with one or more base stations 105.

Processor 820 may include an intelligent hardware device, (e.g., ageneral-purpose processor, a DSP, a central processing unit (CPU), amicrocontroller, an ASIC, an FPGA, a programmable logic device, adiscrete gate or transistor logic component, a discrete hardwarecomponent, or any combination thereof). In some cases, processor 820 maybe configured to operate a memory array using a memory controller. Inother cases, a memory controller may be integrated into processor 820.Processor 820 may be configured to execute computer-readableinstructions stored in a memory to perform various functions (e.g.,functions or tasks supporting uplink resources for beam recovery).

Memory 825 may include random access memory (RAM) and read only memory(ROM). The memory 825 may store computer-readable, computer-executablesoftware 830 including instructions that, when executed, cause theprocessor to perform various functions described herein. In some cases,the memory 825 may contain, among other things, a basic input/outputsystem (BIOS) which may control basic hardware and/or software operationsuch as the interaction with peripheral components or devices.

Software 830 may include code to implement aspects of the presentdisclosure, including code to support uplink resources for beamrecovery. Software 830 may be stored in a non-transitorycomputer-readable medium such as system memory or other memory. In somecases, the software 830 may not be directly executable by the processorbut may cause a computer (e.g., when compiled and executed) to performfunctions described herein.

Transceiver 835 may communicate bi-directionally, via one or moreantennas, wired, or wireless links as described above. For example, thetransceiver 835 may represent a wireless transceiver and may communicatebi-directionally with another wireless transceiver. The transceiver 835may also include a modem to modulate the packets and provide themodulated packets to the antennas for transmission, and to demodulatepackets received from the antennas. In some cases, the wireless devicemay include a single antenna 840. However, in some cases the device mayhave more than one antenna 840, which may be capable of concurrentlytransmitting or receiving multiple wireless transmissions.

I/O controller 845 may manage input and output signals for device 805.I/O controller 845 may also manage peripherals not integrated intodevice 805. In some cases, I/O controller 845 may represent a physicalconnection or port to an external peripheral. In some cases, I/Ocontroller 845 may utilize an operating system such as iOS®, ANDROID®,MS-DOS®, MS-WINDOWS®, OS/2®, UNIX®, LINUX®, or another known operatingsystem. In other cases, I/O controller 845 may represent or interactwith a modem, a keyboard, a mouse, a touchscreen, or a similar device.In some cases, I/O controller 845 may be implemented as part of aprocessor. In some cases, a user may interact with device 805 via I/Ocontroller 845 or via hardware components controlled by I/O controller845.

FIG. 9 shows a block diagram 900 of a wireless device 905 that supportsuplink resources for beam recovery in accordance with various aspects ofthe present disclosure. Wireless device 905 may be an example of aspectsof a base station 105 as described with reference to FIG. 1. wirelessdevice 905 may include receiver 910, base station beam recovery manager915, and transmitter 920. wireless device 905 may also include aprocessor. Each of these components may be in communication with oneanother (e.g., via one or more buses).

Receiver 910 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to uplinkresources for beam recovery, etc.). Information may be passed on toother components of the device. The receiver 910 may be an example ofaspects of the transceiver 1235 described with reference to FIG. 12.

Base station beam recovery manager 915 may be an example of aspects ofthe base station beam recovery manager 1215 described with reference toFIG. 12. Base station beam recovery manager 915 and/or at least some ofits various subcomponents may be implemented in hardware, softwareexecuted by a processor, firmware, or any combination thereof. Ifimplemented in software executed by a processor, the functions of thebase station beam recovery manager 915 and/or at least some of itsvarious subcomponents may be executed by a general-purpose processor, aDSP, an ASIC, an FPGA or other programmable logic device, discrete gateor transistor logic, discrete hardware components, or any combinationthereof designed to perform the functions described in the presentdisclosure.

Base station beam recovery manager 915 and/or at least some of itsvarious subcomponents may be physically located at various positions,including being distributed such that portions of functions areimplemented at different physical locations by one or more physicaldevices. In some examples, base station beam recovery manager 915 and/orat least some of its various subcomponents may be a separate anddistinct component in accordance with various aspects of the presentdisclosure. In other examples, base station beam recovery manager 915and/or at least some of its various subcomponents may be combined withone or more other hardware components, including but not limited to anI/O component, a transceiver, a network server, another computingdevice, one or more other components described in the presentdisclosure, or a combination thereof in accordance with various aspectsof the present disclosure.

Base station beam recovery manager 915 may communicate with one or moreUEs 115 using one or more active beams, transmit a configuration forbeam recovery resources, and receive one or more beam recovery messageson the beam recovery resources, the one or more beam recovery messagesindicating a beam failure of at least one of the one or more activebeams.

Transmitter 920 may transmit signals generated by other components ofthe device. In some examples, the transmitter 920 may be collocated witha receiver 910 in a transceiver module. For example, the transmitter 920may be an example of aspects of the transceiver 1235 described withreference to FIG. 12. The transmitter 920 may include a single antenna,or it may include a set of antennas.

FIG. 10 shows a block diagram 1000 of a wireless device 1005 thatsupports uplink resources for beam recovery in accordance with variousaspects of the present disclosure. Wireless device 1005 may be anexample of aspects of a wireless device 905 or a base station 105 asdescribed with reference to FIGS. 1 and 9. Wireless device 1005 mayinclude receiver 1010, base station beam recovery manager 1015, andtransmitter 1020. Wireless device 1005 may also include a processor.Each of these components may be in communication with one another (e.g.,via one or more buses).

Receiver 1010 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to uplinkresources for beam recovery, etc.). Information may be passed on toother components of the device. The receiver 1010 may be an example ofaspects of the transceiver 1235 described with reference to FIG. 12.

Base station beam recovery manager 1015 may be an example of aspects ofthe base station beam recovery manager 1215 described with reference toFIG. 12. Base station beam recovery manager 1015 and/or at least some ofits various subcomponents may be implemented in hardware, softwareexecuted by a processor, firmware, or any combination thereof. Ifimplemented in software executed by a processor, the functions of thebase station beam recovery manager 1015 and/or at least some of itsvarious subcomponents may be executed by a general-purpose processor, aDSP, an ASIC, an FPGA or other programmable logic device, discrete gateor transistor logic, discrete hardware components, or any combinationthereof designed to perform the functions described in the presentdisclosure.

Base station beam recovery manager 1015 and/or at least some of itsvarious subcomponents may be physically located at various positions,including being distributed such that portions of functions areimplemented at different physical locations by one or more physicaldevices. In some examples, base station beam recovery manager 1015and/or at least some of its various subcomponents may be a separate anddistinct component in accordance with various aspects of the presentdisclosure. In other examples, base station beam recovery manager 1015and/or at least some of its various subcomponents may be combined withone or more other hardware components, including but not limited to anI/O component, a transceiver, a network server, another computingdevice, one or more other components described in the presentdisclosure, or a combination thereof in accordance with various aspectsof the present disclosure. Base station beam recovery manager 1015 mayalso include communication manager 1025, uplink resource manager 1030,and base station beam recovery message manager 1035.

Communication manager 1025 may communicate with one or more UEs 115using one or more active beams. Uplink resource manager 1030 maytransmit a configuration for beam recovery resources. In some examples,uplink resource manager 1030 may transmit an indication that enables theuse of the beam recovery resources for the one or more beam recoverymessages, where receiving beam recovery messages is based on theindication. Alternatively, uplink resource manager 1030 may transmit anindication that disables the use of the beam recovery resources for theone or more beam recovery messages. In some cases, uplink resourcemanager 1030 may identify a mapping between the beam recovery resourcesand the set of downlink beams based on the one or more referencesignals, where the configuration includes an indication of the mapping.

In some cases, transmitting the configuration for the beam recoveryresources includes transmitting the configuration as part of RRCsignaling or as part of a system information broadcast. In some cases,the configuration includes an indication of a set of beams for each ofthe one or more beam recovery messages. In some cases, the beam recoveryresources are associated with a first region of resources that aredifferent from a second region resources allocated for transmission of arandom access message.

Base station beam recovery message manager 1035 may receive one or morebeam recovery messages on the beam recovery resources, the one or morebeam recovery messages indicating a beam failure of at least one of theone or more active beams. In some cases, receiving the one or more beamrecovery messages includes receiving a measurement report from the oneor more UEs 115. In some cases, receiving the one or more beam recoverymessages includes receiving the one or more beam recovery messages on aset of resources in one or more receive beam directions.

Transmitter 1020 may transmit signals generated by other components ofthe device. In some examples, the transmitter 1020 may be collocatedwith a receiver 1010 in a transceiver module. For example, thetransmitter 1020 may be an example of aspects of the transceiver 1235described with reference to FIG. 12. The transmitter 1020 may include asingle antenna, or it may include a set of antennas.

FIG. 11 shows a block diagram 1100 of a base station beam recoverymanager 1115 that supports uplink resources for beam recovery inaccordance with various aspects of the present disclosure. The basestation beam recovery manager 1115 may be an example of aspects of abase station beam recovery manager 1215 described with reference toFIGS. 9, 10, and 12. Base station beam recovery manager 1115 and/or atleast some of its various subcomponents may be implemented in hardware,software executed by a processor, firmware, or any combination thereofIf implemented in software executed by a processor, the functions of thebase station beam recovery manager 1115 and/or at least some of itsvarious subcomponents may be executed by a general-purpose processor, aDSP, an ASIC, an FPGA or other programmable logic device, discrete gateor transistor logic, discrete hardware components, or any combinationthereof designed to perform the functions described in the presentdisclosure.

Base station beam recovery manager 1115 and/or at least some of itsvarious subcomponents may be physically located at various positions,including being distributed such that portions of functions areimplemented at different physical locations by one or more physicaldevices. In some examples, base station beam recovery manager 1115and/or at least some of its various subcomponents may be a separate anddistinct component in accordance with various aspects of the presentdisclosure. In other examples, base station beam recovery manager 1115and/or at least some of its various subcomponents may be combined withone or more other hardware components, including but not limited to anI/O component, a transceiver, a network server, another computingdevice, one or more other components described in the presentdisclosure, or a combination thereof in accordance with various aspectsof the present disclosure. The base station beam recovery manager 1115may include communication manager 1120, uplink resource manager 1125,base station beam recovery message manager 1130, reference signalmanager 1135, beam direction component 1140, uplink signal measurementcomponent 1145, traffic manager 1150, SNR component 1155, and payloadmanager 1160. Each of these modules may communicate, directly orindirectly, with one another (e.g., via one or more buses).

Communication manager 1120 may communicate with one or more UEs 115using one or more active beams. Uplink resource manager 1125 maytransmit a configuration for beam recovery resources. In some examples,uplink resource manager 1125 may transmit an indication that enables theuse of the beam recovery resources for the one or more beam recoverymessages, where receiving beam recovery messages is based on theindication. Alternatively, uplink resource manager 1125 may transmit anindication that disables the use of the beam recovery resources for theone or more beam recovery messages. In some cases, uplink resourcemanager 1125 may identify a mapping between the beam recovery resourcesand the set of downlink beams based on the one or more referencesignals, where the configuration includes an indication of the mapping.

In some cases, transmitting the configuration for the beam recoveryresources includes transmitting the configuration as part of RRCsignaling or as part of a system information broadcast. In some cases,the configuration includes an indication of a set of beams for each ofthe one or more beam recovery messages. In some cases, the beam recoveryresources are associated with a first region of resources that aredifferent from a second region resources allocated for transmission of arandom access message.

Base station beam recovery message manager 1130 may receive one or morebeam recovery messages on the beam recovery resources, the one or morebeam recovery messages indicating a beam failure of at least one of theone or more active beams. In some cases, receiving the one or more beamrecovery messages includes receiving a measurement report from the oneor more UEs 115. In some cases, receiving the one or more beam recoverymessages includes receiving the one or more beam recovery messages on aset of resources in one or more receive beam directions.

Reference signal manager 1135 may transmit a message in response to thereceived one or more beam recovery messages, the message including anindication of a set of reference signals for beam refinement andidentify one or more reference signals associated with a set of downlinkbeams. Beam direction component 1140 may determine a transmit beamdirection based on the measurement report, transmit the message to theUE 115 using the determined transmit beam direction, and determine atransmit beam direction based on the measurement of the uplink signals,where transmitting the message to the UE 115 is based on the transmitbeam direction.

Uplink signal measurement component 1145 may perform a measurement onuplink signals over the one or more active beams. Traffic manager 1150may identify a traffic level associated with a subset of the one or moreUEs 115. In such cases, transmitting the configuration for beam recoveryresources includes transmitting the configuration to the subset of theone or more UEs 115 based on the identified traffic level. SNR component1155 may identify an SNR associated with the UE 115, and theconfiguration may include a UE-specific configuration of beam recoveryresources based on the identified SNR. Payload manager 1160 may identifya payload associated with an uplink transmission from the one or moreUEs 115, where the configuration includes an indication of additionalbeam recovery resources allocated for the one or more beam recoverymessages based on the identified payload.

FIG. 12 shows a diagram of a system 1200 including a device 1205 thatsupports uplink resources for beam recovery in accordance with variousaspects of the present disclosure. Device 1205 may be an example of orinclude the components of base station 105 as described above, e.g.,with reference to FIG. 1. Device 1205 may include components forbi-directional voice and data communications including components fortransmitting and receiving communications, including base station beamrecovery manager 1215, processor 1220, memory 1225, software 1230,transceiver 1235, antenna 1240, network communications manager 1245, andbase station communications manager 1250. These components may be inelectronic communication via one or more busses (e.g., bus 1210). Device1205 may communicate wirelessly with one or more UEs 115.

Processor 1220 may include an intelligent hardware device, (e.g., ageneral-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, anFPGA, a programmable logic device, a discrete gate or transistor logiccomponent, a discrete hardware component, or any combination thereof).In some cases, processor 1220 may be configured to operate a memoryarray using a memory controller. In other cases, a memory controller maybe integrated into processor 1220. Processor 1220 may be configured toexecute computer-readable instructions stored in a memory to performvarious functions (e.g., functions or tasks supporting uplink resourcesfor beam recovery).

Memory 1225 may include RAM and ROM. The memory 1225 may storecomputer-readable, computer-executable software 1230 includinginstructions that, when executed, cause the processor to perform variousfunctions described herein. In some cases, the memory 1225 may contain,among other things, a BIOS which may control basic hardware and/orsoftware operation such as the interaction with peripheral components ordevices.

Software 1230 may include code to implement aspects of the presentdisclosure, including code to support uplink resources for beamrecovery. Software 1230 may be stored in a non-transitorycomputer-readable medium such as system memory or other memory. In somecases, the software 1230 may not be directly executable by the processorbut may cause a computer (e.g., when compiled and executed) to performfunctions described herein.

Transceiver 1235 may communicate bi-directionally, via one or moreantennas, wired, or wireless links as described above. For example, thetransceiver 1235 may represent a wireless transceiver and maycommunicate bi-directionally with another wireless transceiver. Thetransceiver 1235 may also include a modem to modulate the packets andprovide the modulated packets to the antennas for transmission, and todemodulate packets received from the antennas. In some cases, thewireless device may include a single antenna 1240. However, in somecases the device may have more than one antenna 1240, which may becapable of concurrently transmitting or receiving multiple wirelesstransmissions.

Network communications manager 1245 may manage communications with thecore network (e.g., via one or more wired backhaul links). For example,the network communications manager 1245 may manage the transfer of datacommunications for client devices, such as one or more UEs 115.

Base station communications manager 1250 may manage communications withother base stations 105, and may include a controller or scheduler forcontrolling communications with UEs 115 in cooperation with other basestations 105. For example, the base station communications manager 1250may coordinate scheduling for transmissions to UEs 115 for variousinterference mitigation techniques such as beamforming or jointtransmission. In some examples, base station communications manager 1250may provide an X2 interface within an Long Term Evolution (LTE)/LTE-Awireless communication network technology to provide communicationbetween base stations 105.

FIG. 13 shows a flowchart illustrating a method 1300 for uplinkresources for beam recovery in accordance with various aspects of thepresent disclosure. The operations of method 1300 may be implemented bya UE 115 or its components as described herein. For example, theoperations of method 1300 may be performed by a UE beam recovery manageras described with reference to FIGS. 5 through 8. In some examples, a UE115 may execute a set of codes to control the functional elements of thedevice to perform the functions described below. Additionally oralternatively, the UE 115 may perform aspects of the functions describedbelow using special-purpose hardware.

At block 1305 the UE 115 may receive a configuration for beam recoveryresources. The operations of block 1305 may be performed according tothe methods described with reference to FIGS. 1 through 4. In certainexamples, aspects of the operations of block 1305 may be performed by aresource configuration component as described with reference to FIGS. 5through 8.

At block 1310 the UE 115 may identify a beam failure of one or moreactive beams used to communicate with a base station 105. The operationsof block 1310 may be performed according to the methods described withreference to FIGS. 1 through 4. In certain examples, aspects of theoperations of block 1310 may be performed by a beam failure component asdescribed with reference to FIGS. 5 through 8.

At block 1315 the UE 115 may transmit, according to the receivedconfiguration, a beam recovery message to the base station using thebeam recovery resources based on the identified beam failure. Theoperations of block 1315 may be performed according to the methodsdescribed with reference to FIGS. 1 through 4. In certain examples,aspects of the operations of block 1315 may be performed by a UE beamrecovery message manager as described with reference to FIGS. 5 through8.

FIG. 14 shows a flowchart illustrating a method 1400 for uplinkresources for beam recovery in accordance with various aspects of thepresent disclosure. The operations of method 1400 may be implemented bya UE 115 or its components as described herein. For example, theoperations of method 1400 may be performed by a UE beam recovery manageras described with reference to FIGS. 5 through 8. In some examples, a UE115 may execute a set of codes to control the functional elements of thedevice to perform the functions described below. Additionally oralternatively, the UE 115 may perform aspects of the functions describedbelow using special-purpose hardware.

At block 1405 the UE 115 may receive a configuration for beam recoveryresources. The operations of block 1405 may be performed according tothe methods described with reference to FIGS. 1 through 4. In certainexamples, aspects of the operations of block 1405 may be performed by aresource configuration component as described with reference to FIGS. 5through 8.

At block 1410 the UE 115 may identify a beam failure of one or moreactive beams used to communicate with a base station 105. The operationsof block 1410 may be performed according to the methods described withreference to FIGS. 1 through 4. In certain examples, aspects of theoperations of block 1410 may be performed by a beam failure component asdescribed with reference to FIGS. 5 through 8.

At block 1415 the UE 115 may transmit, according to the receivedconfiguration, a beam recovery message to the base station 105 using thebeam recovery resources based on the identified beam failure. Theoperations of block 1415 may be performed according to the methodsdescribed with reference to FIGS. 1 through 4. In certain examples,aspects of the operations of block 1415 may be performed by a UE beamrecovery message manager as described with reference to FIGS. 5 through8.

At block 1420 the UE 115 may receive a message from the base station 105in response to the transmitted beam recovery message, the messageincluding an indication of a set of reference signals for beamrefinement. The operations of block 1420 may be performed according tothe methods described with reference to FIGS. 1 through 4. In certainexamples, aspects of the operations of block 1420 may be performed by abeam refinement component as described with reference to FIGS. 5 through8.

FIG. 15 shows a flowchart illustrating a method 1500 for uplinkresources for beam recovery in accordance with various aspects of thepresent disclosure. The operations of method 1500 may be implemented bya UE 115 or its components as described herein. For example, theoperations of method 1500 may be performed by a UE beam recovery manageras described with reference to FIGS. 5 through 8. In some examples, a UE115 may execute a set of codes to control the functional elements of thedevice to perform the functions described below. Additionally oralternatively, the UE 115 may perform aspects of the functions describedbelow using special-purpose hardware.

At block 1505 the UE 115 may receive a configuration for beam recoveryresources. For example, the configuration may be received via RRCsignaling, or via a system information broadcast. The operations ofblock 1505 may be performed according to the methods described withreference to FIGS. 1 through 4. In certain examples, aspects of theoperations of block 1505 may be performed by a resource configurationcomponent as described with reference to FIGS. 5 through 8.

At block 1510 the UE 115 may optionally receive an indication thatenables the use of the beam recovery resources for the transmission ofthe beam recovery message. For example, the UE 115 may receive via lowerlayer (L1/L2 signaling) an indication to enable the use of the beamrecovery resources. In such cases, the UE 115 may have previouslytransmitted a beam recovery message using a different set of resources(e.g., resources allocated for RACH or SR messages), and upon receivingthe indication enabling the use of dedicated resources for beamrecovery, may thereafter transmit beam recovery messages on the beamrecovery resources. The operations of block 1520 may be performedaccording to the methods described with reference to FIGS. 1 through 4.In certain examples, aspects of the operations of block 1520 may beperformed by a UE beam recovery message manager as described withreference to FIGS. 5 through 8.

Alternatively, at block 1515 the UE 115 may receive an indication thatdisables the use of the beam recovery resources for the transmission ofthe beam recovery message. In such cases, the UE 115 may transmit beamrecovery messages according to, for example, a default scheme orconfiguration for transmitting beam recovery messages on uplinkresources. The operations of block 1515 may be performed according tothe methods described with reference to FIGS. 1 through 4. In certainexamples, aspects of the operations of block 1515 may be performed by aUE beam recovery message manager as described with reference to FIGS. 5through 8.

At block 1520 the UE 115 may identify a beam failure of one or moreactive beams used to communicate with a base station. The operations ofblock 1520 may be performed according to the methods described withreference to FIGS. 1 through 4. In certain examples, aspects of theoperations of block 1520 may be performed by a beam failure component asdescribed with reference to FIGS. 5 through 8.

At block 1525 the UE 115 may transmit, according to the receivedconfiguration, a beam recovery message to the base station using thebeam recovery resources based on the identified beam failure, wheretransmitting the beam recovery message is based on the indication. Theoperations of block 1525 may be performed according to the methodsdescribed with reference to FIGS. 1 through 4. In certain examples,aspects of the operations of block 1525 may be performed by a UE beamrecovery message manager as described with reference to FIGS. 5 through8.

FIG. 16 shows a flowchart illustrating a method 1600 for uplinkresources for beam recovery in accordance with various aspects of thepresent disclosure. The operations of method 1600 may be implemented bya base station 105 or its components as described herein. For example,the operations of method 1600 may be performed by a base station beamrecovery manager as described with reference to FIGS. 9 through 12. Insome examples, a base station 105 may execute a set of codes to controlthe functional elements of the device to perform the functions describedbelow. Additionally or alternatively, the base station 105 may performaspects of the functions described below using special-purpose hardware.

At block 1605 the base station 105 may communicate with one or more UEs115 using one or more active beams. The operations of block 1605 may beperformed according to the methods described with reference to FIGS. 1through 4. In certain examples, aspects of the operations of block 1605may be performed by a communication manager as described with referenceto FIGS. 9 through 12.

At block 1610 the base station 105 may transmit a configuration for beamrecovery resources. The operations of block 1610 may be performedaccording to the methods described with reference to FIGS. 1 through 4.In certain examples, aspects of the operations of block 1610 may beperformed by a uplink resource manager as described with reference toFIGS. 9 through 12.

At block 1615 the base station 105 may receive one or more beam recoverymessages on the beam recovery resources, the one or more beam recoverymessages indicating a beam failure of at least one of the one or moreactive beams. The operations of block 1615 may be performed according tothe methods described with reference to FIGS. 1 through 4. In certainexamples, aspects of the operations of block 1615 may be performed by abase station beam recovery message manager as described with referenceto FIGS. 9 through 12.

FIG. 17 shows a flowchart illustrating a method 1700 for uplinkresources for beam recovery in accordance with various aspects of thepresent disclosure. The operations of method 1700 may be implemented bya base station 105 or its components as described herein. For example,the operations of method 1700 may be performed by a base station beamrecovery manager as described with reference to FIGS. 9 through 12. Insome examples, a base station 105 may execute a set of codes to controlthe functional elements of the device to perform the functions describedbelow. Additionally or alternatively, the base station 105 may performaspects of the functions described below using special-purpose hardware.

At block 1705 the base station 105 may communicate with one or more UEs115 using one or more active beams. The operations of block 1705 may beperformed according to the methods described with reference to FIGS. 1through 4. In certain examples, aspects of the operations of block 1705may be performed by a communication manager as described with referenceto FIGS. 9 through 12.

At block 1710 the base station 105 may transmit, as part of RRCsignaling or a system information broadcast, a configuration for beamrecovery resources. The operations of block 1710 may be performedaccording to the methods described with reference to FIGS. 1 through 4.In certain examples, aspects of the operations of block 1710 may beperformed by a uplink resource manager as described with reference toFIGS. 9 through 12.

At block 1715 the base station 105 may receive one or more beam recoverymessages on the beam recovery resources, the one or more beam recoverymessages indicating a beam failure of at least one of the one or moreactive beams. The operations of block 1715 may be performed according tothe methods described with reference to FIGS. 1 through 4. In certainexamples, aspects of the operations of block 1715 may be performed by abase station beam recovery message manager as described with referenceto FIGS. 9 through 12.

FIG. 18 shows a flowchart illustrating a method 1800 for uplinkresources for beam recovery in accordance with various aspects of thepresent disclosure. The operations of method 1800 may be implemented bya base station 105 or its components as described herein. For example,the operations of method 1800 may be performed by a base station beamrecovery manager as described with reference to FIGS. 9 through 12. Insome examples, a base station 105 may execute a set of codes to controlthe functional elements of the device to perform the functions describedbelow. Additionally or alternatively, the base station 105 may performaspects of the functions described below using special-purpose hardware.

At block 1805 the base station 105 may communicate with one or more UEs115 using one or more active beams. The operations of block 1805 may beperformed according to the methods described with reference to FIGS. 1through 4. In certain examples, aspects of the operations of block 1805may be performed by a communication manager as described with referenceto FIGS. 9 through 12.

At block 1810 the base station 105 may identify one or more referencesignals associated with a set of downlink beams. The operations of block1810 may be performed according to the methods described with referenceto FIGS. 1 through 4. In certain examples, aspects of the operations ofblock 1810 may be performed by a reference signal manager as describedwith reference to FIGS. 9 through 12.

At block 1815 the base station 105 may identify a mapping between beamrecovery resources and the set of downlink beams based on the one ormore reference signals. The operations of block 1815 may be performedaccording to the methods described with reference to FIGS. 1 through 4.In certain examples, aspects of the operations of block 1815 may beperformed by a uplink resource manager as described with reference toFIGS. 9 through 12.

At block 1820 the base station 105 may transmit a configuration for beamrecovery resources, where the configuration includes an indication ofthe mapping. The operations of block 1820 may be performed according tothe methods described with reference to FIGS. 1 through 4. In certainexamples, aspects of the operations of block 1820 may be performed by auplink resource manager as described with reference to FIGS. 9 through12.

At block 1825 the base station 105 may receive one or more beam recoverymessages on the beam recovery resources, the one or more beam recoverymessages indicating a beam failure of at least one of the one or moreactive beams. The operations of block 1825 may be performed according tothe methods described with reference to FIGS. 1 through 4. In certainexamples, aspects of the operations of block 1825 may be performed by abase station beam recovery message manager as described with referenceto FIGS. 9 through 12.

It should be noted that the methods described above describe possibleimplementations, and that the operations and the steps may be rearrangedor otherwise modified and that other implementations are possible.Furthermore, aspects from two or more of the methods may be combined.

Techniques described herein may be used for various wirelesscommunications systems such as CDMA, TDMA, FDMA, OFDMA, single carrierfrequency division multiple access (SC-FDMA), and other systems. Theterms “system” and “network” are often used interchangeably. A CDMAsystem may implement a radio technology such as CDMA2000, UniversalTerrestrial Radio Access (UTRA), etc. CDMA2000 covers IS-2000, IS-95,and IS-856 standards. IS-2000 Releases may be commonly referred to asCDMA2000 1X, 1X, etc. IS-856 (TIA-856) is commonly referred to asCDMA2000 1xEV-DO, High Rate Packet Data (HRPD), etc. UTRA includesWideband CDMA (WCDMA) and other variants of CDMA. A TDMA system mayimplement a radio technology such as Global System for MobileCommunications (GSM).

An OFDMA system may implement a radio technology such as Ultra MobileBroadband (UMB), Evolved UTRA (E-UTRA), Institute of Electrical andElectronics Engineers (IEEE) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE802.20, Flash-OFDM, etc. UTRA and E-UTRA are part of Universal MobileTelecommunications system (UMTS). 3GPP Long Term Evolution (LTE) andLTE-Advanced (LTE-A) are releases of Universal Mobile TelecommunicationsSystem (UMTS) that use E-UTRA. UTRA, E-UTRA, UMTS, LTE, LTE-A, NR, andGSM are described in documents from the organization named “3rdGeneration Partnership Project” (3GPP). CDMA2000 and UMB are describedin documents from an organization named “3rd Generation PartnershipProject 2” (3GPP2). The techniques described herein may be used for thesystems and radio technologies mentioned above as well as other systemsand radio technologies. While aspects an LTE or an NR system may bedescribed for purposes of example, and LTE or NR terminology may be usedin much of the description, the techniques described herein areapplicable beyond LTE or NR applications.

In LTE/LTE-A networks, including such networks described herein, theterm evolved node B (eNB) may be generally used to describe the basestations. The wireless communications system or systems described hereinmay include a heterogeneous LTE/LTE-A or NR network in which differenttypes of evolved node B (eNBs) provide coverage for various geographicalregions. For example, each eNB, gNB or base station may providecommunication coverage for a macro cell, a small cell, or other types ofcell. The term “cell” may be used to describe a base station, a carrieror component carrier associated with a base station, or a coverage area(e.g., sector, etc.) of a carrier or base station, depending on context.

Base stations may include or may be referred to by those skilled in theart as a base transceiver station, a radio base station, an accesspoint, a radio transceiver, a NodeB, eNodeB (eNB), next generation NodeB(gNB), Home NodeB, a Home eNodeB, or some other suitable terminology.The geographic coverage area for a base station may be divided intosectors making up only a portion of the coverage area. The wirelesscommunications system or systems described herein may include basestations of different types (e.g., macro or small cell base stations).The UEs described herein may be able to communicate with various typesof base stations and network equipment including macro eNBs, small celleNBs, gNBs, relay base stations, and the like. There may be overlappinggeographic coverage areas for different technologies.

A macro cell generally covers a relatively large geographic area (e.g.,several kilometers in radius) and may allow unrestricted access by UEswith service subscriptions with the network provider. A small cell is alower-powered base station, as compared with a macro cell, that mayoperate in the same or different (e.g., licensed, unlicensed, etc.)frequency bands as macro cells. Small cells may include pico cells,femto cells, and micro cells according to various examples. A pico cell,for example, may cover a small geographic area and may allowunrestricted access by UEs with service subscriptions with the networkprovider. A femto cell may also cover a small geographic area (e.g., ahome) and may provide restricted access by UEs having an associationwith the femto cell (e.g., UEs in a closed subscriber group (CSG), UEsfor users in the home, and the like). An eNB for a macro cell may bereferred to as a macro eNB. An eNB for a small cell may be referred toas a small cell eNB, a pico eNB, a femto eNB, or a home eNB. An eNB maysupport one or multiple (e.g., two, three, four, and the like) cells(e.g., component carriers).

The wireless communications system or systems described herein maysupport synchronous or asynchronous operation. For synchronousoperation, the base stations may have similar frame timing, andtransmissions from different base stations may be approximately alignedin time. For asynchronous operation, the base stations may havedifferent frame timing, and transmissions from different base stationsmay not be aligned in time. The techniques described herein may be usedfor either synchronous or asynchronous operations.

The downlink transmissions described herein may also be called forwardlink transmissions while the uplink transmissions may also be calledreverse link transmissions. Each communication link describedherein—including, for example, wireless communications system 100 and200 of FIGS. 1 and 2—may include one or more carriers, where eachcarrier may be a signal made up of multiple subcarriers (e.g., waveformsignals of different frequencies).

The description set forth herein, in connection with the appendeddrawings, describes example configurations and does not represent allthe examples that may be implemented or that are within the scope of theclaims. The term “exemplary” used herein means “serving as an example,instance, or illustration,” and not “preferred” or “advantageous overother examples.” The detailed description includes specific details forthe purpose of providing an understanding of the described techniques.These techniques, however, may be practiced without these specificdetails. In some instances, well-known structures and devices are shownin block diagram form in order to avoid obscuring the concepts of thedescribed examples.

In the appended figures, similar components or features may have thesame reference label. Further, various components of the same type maybe distinguished by following the reference label by a dash and a secondlabel that distinguishes among the similar components. If just the firstreference label is used in the specification, the description isapplicable to any one of the similar components having the same firstreference label irrespective of the second reference label.

Information and signals described herein may be represented using any ofa variety of different technologies and techniques. For example, data,instructions, commands, information, signals, bits, symbols, and chipsthat may be referenced throughout the above description may berepresented by voltages, currents, electromagnetic waves, magneticfields or particles, optical fields or particles, or any combinationthereof.

The various illustrative blocks and modules described in connection withthe disclosure herein may be implemented or performed with ageneral-purpose processor, a DSP, an ASIC, an FPGA or other programmablelogic device, discrete gate or transistor logic, discrete hardwarecomponents, or any combination thereof designed to perform the functionsdescribed herein. A general-purpose processor may be a microprocessor,but in the alternative, the processor may be any conventional processor,controller, microcontroller, or state machine. A processor may also beimplemented as a combination of computing devices (e.g., a combinationof a DSP and a microprocessor, multiple microprocessors, one or moremicroprocessors in conjunction with a DSP core, or any other suchconfiguration).

The functions described herein may be implemented in hardware, softwareexecuted by a processor, firmware, or any combination thereof Ifimplemented in software executed by a processor, the functions may bestored on or transmitted over as one or more instructions or code on acomputer-readable medium. Other examples and implementations are withinthe scope of the disclosure and appended claims. For example, due to thenature of software, functions described above can be implemented usingsoftware executed by a processor, hardware, firmware, hardwiring, orcombinations of any of these. Features implementing functions may alsobe physically located at various positions, including being distributedsuch that portions of functions are implemented at different physicallocations. Also, as used herein, including in the claims, “or” as usedin a list of items (for example, a list of items prefaced by a phrasesuch as “at least one of” or “one or more of”) indicates an inclusivelist such that, for example, a list of at least one of A, B, or C meansA or B or C or AB or AC or BC or ABC (i.e., A and B and C). Also, asused herein, the phrase “based on” shall not be construed as a referenceto a closed set of conditions. For example, an exemplary step that isdescribed as “based on condition A” may be based on both a condition Aand a condition B without departing from the scope of the presentdisclosure. In other words, as used herein, the phrase “based on” shallbe construed in the same manner as the phrase “based at least in parton.”

Computer-readable media includes both non-transitory computer storagemedia and communication media including any medium that facilitatestransfer of a computer program from one place to another. Anon-transitory storage medium may be any available medium that can beaccessed by a general purpose or special purpose computer. By way ofexample, and not limitation, non-transitory computer-readable media maycomprise RAM, ROM, electrically erasable programmable read only memory(EEPROM), compact disk (CD) ROM or other optical disk storage, magneticdisk storage or other magnetic storage devices, or any othernon-transitory medium that can be used to carry or store desired programcode means in the form of instructions or data structures and that canbe accessed by a general-purpose or special-purpose computer, or ageneral-purpose or special-purpose processor. Also, any connection isproperly termed a computer-readable medium. For example, if the softwareis transmitted from a website, server, or other remote source using acoaxial cable, fiber optic cable, twisted pair, digital subscriber line(DSL), or wireless technologies such as infrared, radio, and microwave,then the coaxial cable, fiber optic cable, twisted pair, digitalsubscriber line (DSL), or wireless technologies such as infrared, radio,and microwave are included in the definition of medium. Disk and disc,as used herein, include CD, laser disc, optical disc, digital versatiledisc (DVD), floppy disk and Blu-ray disc where disks usually reproducedata magnetically, while discs reproduce data optically with lasers.Combinations of the above are also included within the scope ofcomputer-readable media.

The description herein is provided to enable a person skilled in the artto make or use the disclosure. Various modifications to the disclosurewill be readily apparent to those skilled in the art, and the genericprinciples defined herein may be applied to other variations withoutdeparting from the scope of the disclosure. Thus, the disclosure is notlimited to the examples and designs described herein, but is to beaccorded the broadest scope consistent with the principles and novelfeatures disclosed herein.

What is claimed is:
 1. A method for wireless communication at a userequipment (UE), comprising: receiving a configuration for beam recoveryresources; identifying a beam failure of one or more active beams usedto communicate with a base station; and transmitting, according to thereceived configuration, a beam recovery message to the base stationusing the beam recovery resources based at least in part on theidentified beam failure.
 2. The method of claim 1, further comprising:receiving a message from the base station in response to the transmittedbeam recovery message, the message comprising an indication of a set ofreference signals for beam refinement.
 3. The method of claim 1, whereintransmitting the beam recovery message to the base station comprises:transmitting the beam recovery message on one or more resources in oneor more beam directions.
 4. The method of claim 1, wherein receiving theconfiguration for the beam recovery resources comprises: receiving theconfiguration as part of radio resource control (RRC) signaling from thebase station or as part of a system information broadcast from the basestation.
 5. The method of claim 1, further comprising: receiving anindication that enables or disables the use of the beam recoveryresources for the transmission of the beam recovery message, whereintransmitting the beam recovery message is based at least in part on theindication.
 6. The method of claim 1, wherein the configurationcomprises a UE-specific configuration for the beam recovery resources.7. The method of claim 1, wherein the configuration comprises anindication of a plurality of beams for transmitting the beam recoverymessage, the indication based at least in part on a signal-to-noiseratio (SNR) associated with the UE, and wherein transmitting the beamrecovery message comprises: transmitting the beam recovery message usingat least one of the plurality of beams.
 8. The method of claim 1,wherein the configuration comprises an indication of a system framenumber (SFN) corresponding to the beam recovery resources, a subframeindex (SFI) corresponding to the beam recovery resources, a periodicitycorresponding to the beam recovery resources, one or more resourceelements (REs) corresponding to the beam recovery resources, or acombination thereof
 9. The method of claim 1, wherein the beam recoveryresources occupy a first region of resources that is different from asecond region of resources allocated for transmission of a random accessmessage.
 10. The method of claim 1, wherein the configuration comprisesan indication of a mapping between a downlink beam from the base stationand the beam recovery resources.
 11. The method of claim 1, furthercomprising: transmitting, according to the received configuration, ascheduling request (SR) to the base station using the beam recoveryresources.
 12. The method of claim 1, further comprising: performingmeasurements of a set of reference signals, the set of reference signalsassociated with the one or more active beams, wherein the beam recoverymessage comprises a measurement report based at least in part on theperformed measurements.
 13. The method of claim 12, wherein themeasurement report comprises a reference signal received power (RSRP), areference signal received quality (RSRQ), a channel quality indicator(CQI), a precoding matrix indicator (PMI) a rank, or a combinationthereof.
 14. The method of claim 12, wherein the set of referencesignals comprises a synchronization signal, a mobility reference signal,a channel state information reference signal (CSI-RS), or a combinationthereof.
 15. The method of claim 1, further comprising: determining amobility condition associated with the UE, the mobility condition of theUE comprising a direction of the UE relative to the base station, anorientation of the UE, a distance from the base station, or acombination thereof, wherein the beam recovery message comprises anindication of the mobility condition.
 16. The method of claim 1, furthercomprising: identifying antenna array information corresponding to oneor more antenna arrays located at the UE, the antenna array informationcomprising a number of antenna arrays located at the UE, wherein thebeam recovery message comprises an indication of the antenna arrayinformation.
 17. The method of claim 1, further comprising: determiningan identity of a downlink beam from the base station, wherein the beamrecovery message comprises an indication of the identity of the downlinkbeam.
 18. A method for wireless communication at a base station,comprising: communicating with one or more user equipment (UEs) usingone or more active beams; transmitting a configuration for beam recoveryresources; and receiving one or more beam recovery messages on the beamrecovery resources, the one or more beam recovery messages indicating abeam failure of at least one of the one or more active beams.
 19. Themethod of claim 18, further comprising: transmitting a message to a UEin response to the received one or more beam recovery messages, themessage comprising an indication of a set of reference signals for beamrefinement.
 20. The method of claim 19, wherein receiving the one ormore beam recovery messages comprises receiving a measurement reportfrom the UE, the method further comprising: determining a transmit beamdirection based at least in part on the measurement report; andtransmitting the message to the UE using the determined transmit beamdirection.
 21. The method of claim 19, further comprising: performing ameasurement on uplink signals over the one or more active beams; anddetermining a transmit beam direction based at least in part on themeasurement of the uplink signals, wherein transmitting the message tothe UE is based at least in part on the transmit beam direction.
 22. Themethod of claim 18, wherein receiving the one or more beam recoverymessages comprises: receiving the one or more beam recovery messages ona set of resources in one or more receive beam directions.
 23. Themethod of claim 18, wherein transmitting the configuration for the beamrecovery resources comprises: transmitting the configuration as part ofradio resource control (RRC) signaling or as part of a systeminformation broadcast.
 24. The method of claim 18, further comprising:transmitting an indication that either enables or disables the use ofthe beam recovery resources for the one or more beam recovery messages,wherein receiving the one or more beam recovery messages is based atleast in part on the indication.
 25. The method of claim 18, furthercomprising: identifying a signal-to-noise ratio (SNR) associated with aUE, wherein the configuration comprises a UE-specific configuration ofbeam recovery resources based at least in part on the identified SNR.26. The method of claim 18, wherein the configuration comprises anindication of a plurality of beams for each of the one or more beamrecovery messages.
 27. The method of claim 18, wherein the beam recoveryresources are associated with a first region of resources that aredifferent from a second region resources allocated for transmission of arandom access message.
 28. The method of claim 18, further comprising:identifying one or more reference signals associated with a set ofdownlink beams; and identifying a mapping between the beam recoveryresources and the set of downlink beams based at leSPEast in part on theone or more reference signals, wherein the configuration comprises anindication of the mapping.
 29. An apparatus for wireless communication,in a system comprising: a processor; memory in electronic communicationwith the processor; and instructions stored in the memory and operable,when executed by the processor, to cause the apparatus to: receive aconfiguration for uplink beam recovery resources; identify a beamfailure of one or more active beams used to communicate with a basestation; and transmit, according to the received configuration, a beamrecovery message to the base station using the uplink beam recoveryresources based at least in part on the identified beam failure.
 30. Anapparatus for wireless communication, in a system comprising: aprocessor; memory in electronic communication with the processor; andinstructions stored in the memory and operable, when executed by theprocessor, to cause the apparatus to: communicate with one or more userequipment (UEs) using one or more active beams; transmit a configurationfor beam recovery resources; and receive one or more beam recoverymessages on the beam recovery resources, the one or more beam recoverymessages indicating a beam failure of at least one of the one or moreactive beams.